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15 Nov 2021 • Journal Article • The Journal of Physical Chemistry C
Room Temperature Colloidal Coating of II–VI Nanoplatelets with Quantum Dots
AbstractThe lowtemperature colloidal production of II–VI nanoplatelet heterostructures has stimulated the interest of researchers due to the possible uses of these materials in various optoelectronic devices. Here, we report a roomtemperature coating by CdS or ZnS dots of preprepared CdSe nanoplatelets. The dot coating process made use of a synthesis developed for the formation… show more 
5 Nov 2021 • Journal Article • Physical Review A
Quantum advantage and noise reduction in distributed quantum computing
AbstractDistributed quantum computing can provide substantial noise reduction due to shallower circuits. An experiment illustrates the advantages in the case of a Grover search. This motivates study of the quantum advantage of the distributed version of the Simon and DeutschJozsa algorithms. We show that the distributed Simon algorithm retains the exponential advantage, but
… show more 
25 Oct 2021 • Journal Article • Nature Physics
Evidence of topological boundary modes with topological nodalpoint superconductivity Associated Content
AbstractTopological superconductors are an essential component for topologically protected quantum computation and information processing. Although signatures of topological superconductivity have been reported in heterostructures, material realizations of intrinsic topological superconductors are rather rare. Here we use scanning tunnelling spectroscopy to study the transition
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21 Oct 2021 • Preprint • arXiv
Quantum measurement with recycled photons
AbstractWe study a device composed of an optical interferometer integrated with a ferrimagnetic sphere resonator (FSR). Magnetooptic coupling can be employed in such a device to manipulate entanglement between optical pulses that are injected into the interferometer and the FSR. The device is designed to allow measuring the lifetime of such macroscopic entangled states in… show more 
20 Oct 2021 • Preprint • arXiv
The mean field approximation and disentanglement
AbstractThe mean field approximation becomes applicable when entanglement is sufficiently weak. We explore a nonlinear term that can be added to the Schr\"{o}dinger equation without violating unitarity of the time evolution. We find that the added term suppresses entanglement, without affecting the evolution of any product state. The dynamics generated by the modified… show more 
12 Oct 2021 • Preprint • arXiv
A deterministic source of indistinguishable photons in a cluster state
AbstractMeasurementbased quantum communication relies on the availability of highly entangled multiphoton cluster states. The inbuilt redundancy in the cluster allows communication between remote nodes using repeated local measurements, compensating for photon losses and probabilistic Bellmeasurements. For feasible applications, the cluster generation should be fast… show more 
7 Oct 2021 • Preprint • arXiv
Generalized FresnelFloquet equations for driven quantum materials
AbstractOptical drives at terahertz and midinfrared frequencies in quantum materials are increasingly used to reveal the nonlinear dynamics of collective modes in correlated manybody systems and their interplay with electromagnetic waves. Recent experiments demonstrated several surprising optical properties of transient states induced by driving, including the appearance of… show more 
7 Oct 2021 • Journal Article • Npj Computational Materials
Method for assessing atomic sources of flicker noise in superconducting qubits
AbstractFlicker noise causes decoherence in Josephson junctionbased superconducting qubits, thus limiting their practical potential as building blocks for quantum computers. This is due to limited length and complexity of executable algorithms, and increased dependency on errorcorrecting measures. Therefore, identifying and subsiding the atomic sources of flicker noise are
… show more 
4 Oct 2021 • Preprint • arXiv
Mode coupling, bistability, and spectral broadening in buckled nanotube resonators
AbstractBistable mechanical resonators play a significant role in various applications, such as sensors, memory elements, and quantum computing. While carbon nanotube (CNT) based resonators have been widely investigated as promising nano electromechanical devices, a bistable CNT resonator has never been demonstrated. Here, we report a new class of CNT resonators in which… show more 
30 Sep 2021 • Journal Article • Applied Physics Letters
Prospects in xray science emerging from quantum optics and nanomaterials
AbstractThe science of xrays is by now over 125 years old, starting with Wilhelm Röntgen's discovery of xrays in 1895, for which Röntgen was awarded the first Nobel Prize in Physics. Xrays have fundamentally changed the world in areas, including medical imaging, security scanners, industrial inspection, materials development, and drugs spectroscopy. Xray science has been… show more 
30 Sep 2021 • Preprint • arXiv
Illustrating quantum information with quantum candies
AbstractThe field of quantum information is becoming more known to the general public. However, effectively demonstrating the concepts underneath quantum science and technology to the general public can be a challenging job. We investigate, extend, and much expand here "quantum candies" (invented by Jacobs), a pedagogical model for intuitively describing some basic concepts in… show more 
21 Sep 2021 • Journal Article • Progress in Quantum Electronics
On the principle operation of tunneling injection quantum dot lasers
AbstractThe concept of tunneling injection was introduced in the 1990's to improve the dynamical properties of semiconductor lasers by avoiding the problem of hot carrier injection which increase the gain nonlinearity and hence limit the modulation capabilities. Indeed, tunneling injection led to record modulation speeds in quantum well lasers. Employing tunneling injection in
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18 Sep 2021 • Book Chapter • Quantum Dot Photodetectors
TwoDimensional MaterialBased Quantum Dots for WavelengthSelective, Tunable, and Broadband Photodetector Devices
AbstractThe rise of atomically thin twodimensional (2D) materials brings a revolution in material science and engineering, and encouraged worldwide scientists to integrate desired 2D materials into electrical circuitry by noncovalent interactions. Regardless of some unique properties including superflexibility, broadband absorption and high carrier mobility, the weak optical… show more 
17 Sep 2021 • Journal Article • Science
Imprinting the quantum statistics of photons on free electrons
AbstractThe interaction between free electrons and light stands at the base of both classical and quantum physics, with applications in freeelectron acceleration, radiation sources, and electron microscopy. Yet to this day, all experiments involving freeelectron–light interactions are fully explained by describing the light as a classical wave. We observed quantum statistics… show more 
17 Sep 2021 • Journal Article • New Journal of Physics
Selection rules for breaking selection rules
AbstractFloquet systems often exhibit dynamical symmetries (DS) that govern the timedependent dynamics and result in selection rules. When a DS is broken, selection rule deviations are expected. Typically, information about the symmetrybreaking perturbation/phase and the timedependent dynamics can be extracted from these deviations, hence they are regarded as a background… show more 
6 Sep 2021 • Journal Article • Nature Communications
Electronic Floquet gyroliquid crystal
AbstractFloquet engineering uses coherent timeperiodic drives to realize designer band structures ondemand, thus yielding a versatile approach for inducing a wide range of exotic quantum manybody phenomena. Here we show how this approach can be used to induce nonequilibrium correlated states with spontaneously broken symmetry in lightly doped semiconductors. In the presence… show more 
25 Aug 2021 • Journal Article • Physical Review Letters
SyntheticSpace Photonic Topological Insulators Utilizing Dynamically Invariant Structure
AbstractSyntheticspace topological insulators are topological systems with at least one spatial dimension replaced by a periodic arrangement of modes, in the form of a ladder of energy levels, cavity modes, or some other sequence of modes. Such systems can significantly enrich the physics of topological insulators, in facilitating higher dimensions, nonlocal coupling, and more… show more 
24 Aug 2021 • Journal Article • Applied Physics Letters
Nonvolatile voltagetunable ferroelectricsuperconducting quantum interference memory devices
AbstractSuperconductivity serves as a unique solidstate platform for electron interference at a devicerelevant lengthscale, which is essential for quantum information and sensing technologies. As opposed to semiconducting transistors that are operated by voltage biasing at the nanometer scale, superconductive quantum devices cannot sustain voltage and are operated with magnetic… show more 
19 Aug 2021 • Preprint • arXiv
Demonstration of an entangling gate between noninteracting qubits using the Quantum Zeno effect
AbstractThe Zeno effect occurs in quantum systems when a very strong measurement is applied, which can alter the dynamics in nontrivial ways. Despite being dissipative, the dynamics stay coherent within any degenerate subspaces of the measurement. Here we show that such a measurement can turn a singlequbit operation into a two or multiqubit entangling gate, even in a… show more 
19 Aug 2021 • Preprint • arXiv
Optimal shorttime measurements for Hamiltonian learning
AbstractCharacterizing noisy quantum devices requires methods for learning the underlying quantum Hamiltonian which governs their dynamics. Often, such methods compare measurements to simulations of candidate Hamiltonians, a task which requires exponential computational complexity. Here, we analyze and optimize a method which circumvents this difficulty using measurements of… show more 
15 Aug 2021 • Preprint • arXiv
On the carrier transport and radiative recombination mechanisms in tunneling injection quantum dot lasers
AbstractWe report temperaturedependent currentvoltage (I  V  T) and output light powervoltage or current (P  V  T) or (P  I  T) characteristics of 1550 nm tunneling injection quantum dot (TI QD) laser diodes. Experimental data is accompanied by physical models that distinguish between different current flow and light emission mechanisms for different applied voltages… show more 
12 Aug 2021 • Preprint • arXiv
Quantum tomography of entangled spinmultiphoton states
AbstractWe present a novel method for quantum tomography of multiqubit states. We apply the method to spinmultiphoton states, which we produce by periodic excitation of a semiconductor quantumdot confined spin every 1/4 of its coherent precession period. These timed excitations lead to the deterministic generation of strings of entangled photons in a cluster state. We show… show more 
11 Aug 2021 • Preprint • arXiv
The coherence of quantum dot confined electron and holespin in low external magnetic field
AbstractWe investigate experimentally and theoretically the temporal evolution of the spin of the conduction band electron and that of the valence band heavy hole, both confined in the same semiconductor quantum dot. In particular, the coherence of the spin purity in the limit of a weak externally applied magnetic field, comparable in strength to the Overhauser field due to… show more 
11 Aug 2021 • Science Advances
Orbital angular momentum multiplication in plasmonic vortex cavities
AbstractOrbital angular momentum of light is a core feature in photonics. Its confinement to surfaces using plasmonics has unlocked many phenomena and potential applications. Here, we introduce the reflection from structural boundaries as a new degree of freedom to generate and control plasmonic orbital angular momentum. We experimentally demonstrate plasmonic vortex cavities… show more 
5 Aug 2021 • Preprint • arXiv
Realizing anomalous Floquet insulators via Chern band annihilation
AbstractTwodimensional periodically driven systems can host an unconventional topological phase unattainable for equilibrium systems, termed the Anomalous FloquetAnderson insulator (AFAI). The AFAI features a quasienergy spectrum with chiral edge modes and a fully localized bulk, leading to nonadiabatic but quantized charge pumping. Here, we show how such a Floquet phase… show more 
5 Aug 2021 • Journal Article • Physical Review Letters
Superradiance and Subradiance due to Quantum Interference of Entangled Free Electrons
AbstractWhen multiple quantum emitters radiate, their emission rate may be enhanced or suppressed due to collective interference in a process known as super or subradiance. Such processes are well known to occur also in light emission from free electrons, known as coherent cathodoluminescence. Unlike atomic systems, free electrons have an unbounded energy spectrum, and, thus… show more 
30 Jul 2021 • Conference Paper • Microscopy and Microanalysis
Extreme LightMatter Interactions in the Ultrafast Transmission Electron Microscope
AbstractOver the past few years, quantized interactions between coherent free electrons and femtosecond laser pulses have shown intriguing new prospects for lightmatter interactions. The talk will present theory and experiments of free electrons in laserdriven (ultrafast) transmission electron microscopy. Our experiment achieved what is, in many respects, the most powerful… show more 
20 Jul 2021 • Journal Article • Physical Review D
Experimental observation of accelerationinduced thermality
AbstractWe examine the radiation emitted by highenergy positrons channeled into silicon crystal samples. The positrons are modeled as semiclassical vector currents coupled to an UnruhDeWitt detector to incorporate any local change in the energy of the positron. In the subsequent accelerated QED analysis, we discover a Larmor formula and power spectrum that are both thermalized… show more 
20 Jul 2021 • Journal Article • Physical Review Research
Roomtemperature coherent revival in an ensemble of quantum dots
Roomtemperature coherent revival in an ensemble of quantum dotsSemiconductor quantum dots (QDs) are nanocrystals with atomlike delta function density of states and discrete energy levels. Advancements in fabrication led to record QD homogeneity and implementation in semiconductor laser structures which exhibit remarkable properties highlighted by ultranarrow spectral emission and temperatureinsensitive operation. An emergingAbstractWe demonstrate the hallmark concept of periodic collapse and revival of coherence in a roomtemperature ensemble of quantum dots (QDs) in the form of a 1.5mmlong optical amplifier. Femtosecond excitation pulses induce coherent interactions with a number of discrete homogeneous QD subgroups within an inhomogeneously broadened ensemble, which interfere constructively… show more 
30 Jun 2021 • Journal Article • Advances in Optics and Photonics
Topological photonics in synthetic dimensions
AbstractTopological photonics is a new and rapidly growing field that deals with topological phases and topological insulators for light. Recently, the scope of these systems was expanded dramatically by incorporating nonspatial degrees of freedom. These synthetic dimensions can range from a discrete ladder of cavity modes or Bloch modes of an array of waveguides to a timebin… show more 
22 Jun 2021 • Preprint • arXiv
Towards an independent determination of muon g2 from muonium spectroscopy
AbstractWe show that muonium spectroscopy in the coming years can reach a precision high enough to determine the anomalous magnetic moment of the muon below one part per million (ppm). Such an independent determination of muon g2, which is not limited by hadronic uncertainties, would certainly shed light on the 2ppm difference currently observed between spinprecession… show more 
14 Jun 2021 • Preprint • arXiv
Onedimensional ghost imaging with an electron microscope: a route towards ghost imaging with inelastically scattered electrons
AbstractIn quantum mechanics, entanglement and correlations are not just a mere sporadic curiosity, but rather common phenomena at the basis of an interacting quantum system. In electron microscopy, such concepts have not been extensively explored yet in all their implications; in particular, inelastic scattering can be reanalyzed in terms of correlation between the electron… show more 
11 Jun 2021 • Journal Article • Science
Spatiotemporal imaging of 2D polariton wave packet dynamics using free electrons
AbstractCoherent optical excitations in twodimensional (2D) materials, 2D polaritons, can generate a plethora of optical phenomena that arise from the extraordinary dispersion relations that do not exist in regular materials. Probing of the dynamical phenomena of 2D polaritons requires simultaneous spatial and temporal imaging capabilities and could reveal unknown coherent… show more 
11 Jun 2021 • Journal Article • Physical Review Letters
Toward AtomicResolution Quantum Measurements with Coherently Shaped Free Electrons
AbstractFree electrons provide a powerful tool for probing material properties at atomic resolution. Recent advances in ultrafast electron microscopy enable the manipulation of freeelectron wave functions using laser pulses. It would be of great importance if one could combine the spatial resolution of electron microscopes with the ability of laser pulses to probe coherent… show more 
8 Jun 2021 • Journal Article • eLight
Highlighting photonics: looking into the next decade
AbstractLet there be light–to change the world we want to be! Over the past several decades, and ever since the birth of the first laser, mankind has witnessed the development of the science of light, as lightbased technologies have revolutionarily changed our lives. Needless to say, photonics has now penetrated into many aspects of science and technology, turning into an… show more 
8 Jun 2021 • Poster • Proceedings of Electron Beam Spectroscopy for Nanooptics 2021 (EBSN2021)
Achieving SingleElectron–SinglePhoton Interaction in a Transmission Electron Microscope Using 2D Cherenkov Radiation
AbstractOver 80 years of research into freeelectron radiation have not yet changed its popular description as a threedimensional, classical electromagnetic wave1–5, best exemplified by the Cherenkov effect – the radiation of charged particles exceeding the speed of light in a medium1,6. Freeelectron radiation was predicted to fundamentally change in reduced dimensionality7–9… show more 
4 Jun 2021 • Conference Paper • 52nd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Employing deep neural networks in the analysis of visual data in ultracold atoms experiments
AbstractDeep learning reconstruction models enable the analysis of noisy physical data with unparalleled accuracy. These tools prove to be extremely useful when analyzing absorption imaging signals that suffer from structural structured noise due to slow changes in the illumination. Most of this noise can be removed by taking two successive exposures. Even then, some noise… show more 
3 Jun 2021 • Journal Article • SciPost Physics
Hierarchy of manybody invariants and quantized magnetization in anomalous Floquet insulators
AbstractWe uncover a new family of fewbody topological phases in periodically driven fermionic systems in two dimensions. These phases, which we term correlationinduced anomalous Floquet insulators (CIAFIs), are characterized by quantized contributions to the bulk magnetization from multiparticle correlations, and are classified by a family of integervalued topological… show more 
2 Jun 2021 • Conference Paper • 52nd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Progress on the JILA Gen. III eEDM Experiment
AbstractThe third generation (Gen. III) apparatus for the measurement of the electron electric dipole moment (eEDM) at JILA utilizes ThF+, rather than HfF+, because: (i) the eEDM sensitive state of ThF+ promises a longer coherence time (~ 20 seconds) [1,2], and (ii) its 50% larger effective electric field increases eEDM sensitivity [3,4]. The “conveyor belt” of 100 consecutive… show more 
2 Jun 2021 • Conference Paper • 52nd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Projected Sensitivity of the JILA Gen. II eEDM Experiment
AbstractA new limit on the permanent electric dipole moment of the electron (eEDM) will probe physics beyond the standard model and shed light on open questions such as the baryon asymmetry and dark matter. Our upcoming measurement of the eEDM uses a thermal cloud of HfF+ ions held in an RF trap, allowing us to leverage secondscale coherence times and the large internal electric… show more 
2 Jun 2021 • Conference Paper • 52nd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Characterization of systematic shifts in the 2 nd generation JILA eEDM experiment
AbstractTo improve our nuclear beta decay asymmetry experiment [B. Fenker et al. Phys. Rev. Lett. 120 062502 (2018)]), we are trying to improve the vector polarization of our lasercooled atoms from our present 99.1 + 0.1% [B. Fenker et al. New J. Phys 18 073028 (2016)]. We cycle on and off a MOT, and optically pump 37K atoms with trap off. We use circularly polarized light… show more 
1 Jun 2021 • Conference Paper • 52nd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Quantum speed limits crossover probed by matter wave interferometry
AbstractQuantum speed limits dictate the rate of quantum state evolution and thus restrict the maximal performance of any quantum technology. The two most celebrated limits are formulated in terms of the state's energy uncertainty (MandelstamTam bound) and average energy (MargolusLevitin bound). We perform matter wave interferometry experiments and track the motion of a single… show more 
27 May 2021 • Journal Article • Physical Review A
Stability of the Grabert master equation
AbstractWe study the dynamics of a quantum system having Hilbert space of finite dimension d_{H} . Instabilities are possible provided that the master equation governing the system's dynamics contain nonlinear terms. Here we consider the nonlinear master equation derived by Grabert. The dynamics near a fixed point is analyzed by using the method of linearization, and by evaluating the… show more 
25 May 2021 • Journal Article • Quantum Materials
Critical charge fluctuations and emergent coherence in a strongly correlated excitonic insulator
AbstractExcitonic insulator is a coherent electronic phase that results from the formation of a macroscopic population of bound particlehole pairs  excitons. With only a few candidate materials known, the collective excitonic behavior is challenging to observe, being obscured by crystalline lattice effects. Here we use polarizationresolved Raman spectroscopy to reveal the… show more 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Subwavelength Spin Excitations Driven by Stimulated Raman Transitions in Ultracold Gases
AbstractWe present subwavelength periodic spin textures of spatially varying Raman Rabi frequency created by evanescentwave optical lattice. Our results open the door to the study of spin excitation dynamics in ultracold gases. 
14 May 2021 • Conference Paper • CLEO: Science and Innovations 2021
CoherentlyShaped Free Electrons as HighResolution Probes of Coherence in Quantum Systems
AbstractWe propose a novel technique that leverages free electrons coherentlyshaped by laser pulses to measure quantum coherence in materials, opening the way toward the full characterization of the state of quantum systems at atomicscale resolution. 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Observation of 2D Cherenkov radiation and its Quantized Photonic Nature Using FreeElectrons
AbstractUsing a dispersionengineered structure supporting hybrid photonicplasmonic surface polaritons, we present the first observation of 2D Cherenkov radiation from free electrons, with recordstrong electron–polariton quantum coupling that reaches the singleelectronsinglephoton interaction regime. 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Ultrafast nondestructive measurement of the quantum state of light with free electrons
AbstractWe demonstrate that free electrons can be used as ultrafast nondestructive photon detectors. Particularly, we show how one can measure photon statistics, temporal coherence, and implement full quantum state tomography using free electrons. 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
The FockState Laser: Macroscopic Quantum States of Light Based on Deep Strong LightMatter Coupling
AbstractWe show that coupled lightmatter systems reaching the deep strong coupling regime can be coupled to gain media to form novel types of lasers emitting macroscopic quantum states of light, e.g. manyphoton Fock states. 
14 May 2021 • Conference Paper • Conference on Lasers and Electro Optics
Free Electrons Can Induce Quantum Correlations Between Two Separate Photonic Cavities
AbstractWe find that free electrons passing through two independent photonic cavities induce quantum correlations between them, creating nonzero quantum mutual information and secondorder coherence. The concept is general and applicable for example in electronphonon interactions. 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Photonic Topological Insulators Controlled by Nonlocal Nonlinearity in Synthetic Dimensions
AbstractWe study nonlinear effects in synthetic space photonic topological insulators. This nonlinearity is nonlocal in the synthetic dimensions. We study timeperiodic solitons making a cyclotronlike motion in the synthetic space bulk. 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science
Manipulating Single Surface Plasmon Polariton via Tailored AtomPhoton Interaction
AbstractWe study the interaction of a single surface plasmon polariton with a finite number of atoms and with an infinite atomic lattice. Using only twolevel atoms, we achieve subscattering, superscattering, and electromagnetically induced transparency (EIT). 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
The Synthetic Hilbert Space of LaserDriven FreeElectrons
AbstractWe propose the concept of freeelectrons carrying qudits. We find how electron–laser interactions can shape the electron energy states into arbitrarilylarge synthetic Hilbert spaces, exemplified here for size4. 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Quantum optics in stronglydriven manybody systems
AbstractWe develop the quantum theory of collective light emission in stronglydriven manybody systems. We show how quantum correlations of the emitters can be transferred to the emitted light, leading to generation of nonclassical manyphoton states. 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Superradiant Cathodoluminescence
AbstractWe find that laserdriven freeelectrons can be coherentlyshaped to induce superradiance from manybody quantum emitters. This effect provides new capabilities in electron microscopy&spectroscopy, using high spatiotemporal resolution for coherent control and enhancement of cathodoluminescence. 
14 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Quantumtoclassical transition of lasershaped ultrafast free electrons in phase space
AbstractHere, we propose a SmithPurcell model for shaping free electrons with laser. We find that the quantum interference and deformation of the modulated electrons in phase space are vital for understanding the quantumtoclassical transition. 
14 May 2021 • Conference Paper • CLEO: QELS_Fundamental Science 2021
Superradiant and subradiant light emission from entangled free electrons
AbstractWe show how quantum correlations such as entanglement give rise to a new quantum regime of superradaince and subradiance from freeelectrons, demonstrating that light emission can be sensitive to the quantum state of manybody wavefunctions. 
13 May 2021 • Journal Article • Nature Communications
Combining density functional theory with macroscopic QED for quantum lightmatter interactions in 2D materials
AbstractA quantitative and predictive theory of quantum lightmatter interactions in ultra thin materials involves several fundamental challenges. Any realistic model must simultaneously account for the ultraconfined plasmonic modes and their quantization in the presence of losses, while describing the electronic states from first principles. Herein we develop such a framework… show more 
12 May 2021 • Journal Article • Light: Science & Applications
Creating heralded hyperentangled photons using Rydberg atoms
AbstractEntangled photon pairs are a fundamental component for testing the foundations of quantum mechanics, and for modern quantum technologies such as teleportation and secured communication. Current stateoftheart sources are based on nonlinear processes that are limited in their efficiency and wavelength tunability. This motivates the exploration of physical mechanisms… show more 
9 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Imprinting the quantum statistics of photons on free electrons
AbstractWe observe for the first time the breakdown of the wave nature of light in freeelectronlight interactions. Our experiment demonstrates a new way of measuring quantum states of light using high precision electron energy spectroscopy. 
9 May 2021 • Conference Paper • CLEO: QELS Fundamental Science 2021
Shaping Quantum Photonic States Using Free Electrons
AbstractWe propose a new scheme for creating desired quantum photonic states using interactions of free electrons with optical cavities. We show how the choice of the initial electron state controls the resulting quantum light state. 
May 2021 • Preprint • 2021 Conference on Lasers and ElectroOptics (CLEO)
Light emission by free electrons in photonic timecrystals
AbstractWe study emission of electrons moving in photonic timecrystals, and find exponentially enhanced Cherenkov emission in the momentum gap drawing energy from the modulation, and suppressed emission in the opposite direction due to avoided crossing. © 2021 The Author(s).

30 Apr 2021 • Journal Article • Science Advances
The coherence of light is fundamentally tied to the quantum coherence of the emitting particle
AbstractCoherent emission of light by free charged particles is believed to be successfully captured by classical electromagnetism in all experimental settings. However, recent advances triggered fundamental questions regarding the role of the particle wave function in these processes. Here, we find that even in seemingly classical experimental regimes, light emission is… show more 
29 Apr 2021 • Preprint • arXiv
Vortex beams of atoms and molecules
AbstractAngular momentum plays a central role in a multitude of phenomena in quantum mechanics, recurring in every length scale from the microscopic interactions of light and matter to the macroscopic behavior of superfluids. Vortex beams, carrying intrinsic orbital angular momentum (OAM), are now regularly generated with elementary particles such as photons and electrons, and… show more 
14 Apr 2021 • Journal Article • Journal of Applied Physics
Performance analysis of diamondbased masers
AbstractMasers, the microwave analog of lasers, are an important class of devices that can be used to generate highly coherent and stable microwave signals as well as quantumlimited amplification of microwave photons. Recently, the interest in such devices has increased, probably owing to experiments demonstrating the successful operation at room temperature of solidstate… show more 
14 Apr 2021 • Preprint • arXiv
Failed excitonic quantum phase transition in Ta2Ni(Se1−xSx)5
AbstractWe study the electronic phase diagram of the excitonic insulator candidates Ta2Ni(Se1−xSx)5 [x=0, ... ,1] using Raman spectroscopy. Critical excitonic fluctuations are observed, that diminish with x and ultimately shift to high energies, characteristic of a quantum phase transition. Nonetheless, a symmetrybreaking transition at finite temperatures is detected for all… show more 
12 Apr 2021 • Preprint • arXiv
Observing crossover between quantum speed limits
AbstractQuantum mechanics sets fundamental limits on how fast quantum states can be transformed in time. Two wellknown quantum speed limits are the MandelstamTamm and the MargolusLevitin bounds, which relate the maximum speed of evolution to the system's energy uncertainty and mean energy, respectively. Here, we test concurrently both limits in a multilevel system by… show more 
29 Mar 2021 • Preprint • arXiv
Prethermalization and entanglement dynamics in interacting topological pumps
AbstractWe investigate the formation of quasisteady states in onedimensional pumps of interacting fermions at noninteger filling fraction, in the regime where the driving frequency and interaction strength are small compared to the instantaneous singleparticle band gap throughout the driving cycle. The system rapidly absorbs energy from the driving field, and approaches a… show more 
24 Mar 2021 • Conference Paper • Fractal Geometry and Stochastics VI
Breaking of Continuous Scale Invariance to Discrete Scale Invariance: A Universal Quantum Phase Transition
AbstractWe provide a review on the physics associated with phase transitions in which continuous scale invariance is broken into discrete scale invariance. The rich features of this transition characterized by the abrupt formation of a geometric ladder of eigenstates, low energy universality without fixed points, scale anomalies and Berezinskii–Kosterlitz–Thouless scaling are
… show more 
17 Mar 2021 • Journal Article • Nature Communications
Control of quantum electrodynamical processes by shaping electron wavepackets
AbstractFundamental quantum electrodynamical (QED) processes, such as spontaneous emission and electronphoton scattering, encompass phenomena that underlie much of modern science and technology. Conventionally, calculations in QED and other field theories treat incoming particles as singlemomentum states, omitting the possibility that coherent superposition states, i.e.… show more 
16 Mar 2021 • Conference Paper • Bulletin of the American Physical Society
Customizable neuralnetwork states for topological phases
AbstractThe theory of open quantum systems is crucial for quantum science and engineering. Simulations of such systems are computationally expensive due to the exponential growth of the extended Hilbert spaces' dimensionality. We propose an efficient machine learning approach to simulate such dynamics using a probabilistic formulation of quantum mechanics based on the positive… show more 
16 Mar 2021 • Conference Paper • Bulletin of the American Physical Society
SpinExcitations of 1TTaS2 and Related Magnetoresistance in the 4Hb Phase
AbstractSpinspin interactions can lead to exotic ground states with emergent excitations in frustrated quantum magnets. Such a system is the transition metal dichalcogenide TaS2. While the 1T phase of the material is electrically insulating and exhibits no magnetic ordering down to millikelvin temperatures, the specific heat has a linear fermionictype contribution that suggests… show more 
16 Mar 2021 • Conference Paper • Bulletin of the American Physical Society
Observation of a Smooth PolaronMolecule Transition in a Degenerate Fermi Gas
AbstractUnderstanding the behavior of a spin impurity stronglyinteracting with a Fermi sea is a longstanding challenge in manybody physics. For shortrange interactions and zero temperature, most theories predict a firstorder phase transition between a polaronic ground state and a molecular one. We study this question with an ultracold Fermi gas, utilizing a novel… show more 
12 Mar 2021 • Journal Article • Nature Communications
Insitu observation of trapped carriers in organic metal halide perovskite films with ultrafast temporal and ultrahigh energetic resolutions
AbstractWe insitu observe the ultrafast dynamics of trapped carriers in organic methyl ammonium lead halide perovskite thin films by ultrafast photocurrent spectroscopy with a sub25 picosecond time resolution. Upon ultrafast laser excitation, trapped carriers follow a phonon assisted tunneling mechanism and a hopping transport mechanism along ultrashallow to shallow trap… show more 
12 Mar 2021 • Journal Article • Physical Review Research
Tensor networks contraction and the belief propagation algorithm
AbstractBelief propagation is a wellstudied messagepassing algorithm that runs over graphical models and can be used for approximate inference and approximation of local marginals. The resulting approximations are equivalent to the BethePeierls approximation of statistical mechanics. Here, we show how this algorithm can be adapted to the world of projectedentangledpairstate… show more 
10 Mar 2021 • Journal Article • Science Advances
Shaping Quantum Photonic States Using Free Electrons
AbstractIt is a longstanding goal to create light with unique quantum properties such as squeezing and entanglement. We propose the generation of quantum light using freeelectron interactions, going beyond their already ubiquitous use in generating classical light. This concept is motivated by developments in electron microscopy, which recently demonstrated quantum freeelectron… show more 
8 Mar 2021 • Preprint • arXiv
CorrelationEnhanced Neural Networks as Interpretable Variational Quantum States
AbstractVariational methods have proven to be excellent tools to approximate ground states of complex many body Hamiltonians. Generic tools like neural networks are extremely powerful, but their parameters are not necessarily physically motivated. Thus, an efficient parametrization of the wavefunction can become challenging. In this letter we introduce a neuralnetwork based… show more 
3 Mar 2021 • Preprint • arXiv
An area law for 2D frustrationfree spin systems
AbstractWe prove that the entanglement entropy of the ground state of a locally gapped frustrationfree 2D lattice spin system satisfies an area law with respect to a vertical bipartition of the lattice into left and right regions. We first establish that the ground state projector of any locally gapped frustrationfree 1D spin system can be approximated to within error ϵ by… show more 
1 Mar 2021 • Journal Article • Science Advances
Shaping quantum photonic states using free electrons
AbstractIt is a longstanding goal to create light with unique quantum properties such as squeezing and entanglement. We propose the generation of quantum light using freeelectron interactions, going beyond their already ubiquitous use in generating classical light. This concept is motivated by developments in electron microscopy, which recently demonstrated quantum freeelectron… show more 
26 Feb 2021 • Preprint • arXiv
Comment on: "Nonlinear quantum effects in electromagnetic radiation of a vortex electron"
AbstractThis comment on the Phys. Rev. A paper "Nonlinear quantum effects in electromagnetic radiation of a vortex electron" by Karlovets and PupasovMaximov [Phys. Rev. A 103, 12214 (2021)] addresses their criticism of the combined experimental and theoretical study "Observing the quantum wave nature of free electrons through spontaneous emission" by Remez et al, published in… show more 
26 Feb 2021 • Journal Article • Nature Communications
Complex plasmonexciton dynamics revealed through quantum dot light emission in a nanocavity
AbstractPlasmonic cavities can confine electromagnetic radiation to deep subwavelength regimes. This facilitates strong coupling phenomena to be observed at the limit of individual quantum emitters. Here, we report an extensive set of measurements of plasmonic cavities hosting one to a few semiconductor quantum dots. Scattering spectra show Rabi splitting, demonstrating that… show more 
18 Feb 2021 • Preprint • arXiv
Absence of heating in a uniform Fermi gas created by periodic driving
AbstractUltracold atoms are a powerful resource for quantum technologies. As such, they are usually confined in an external potential that often depends on the atomic spin, which may lead to inhomogeneous broadening, phase separation and decoherence. Dynamical decoupling provides an approach to mitigate these effects by applying an external field that induces rapid spin rotations… show more 
17 Feb 2021 • Journal Article • Nature Communications
Emulating spin transport with nonlinear optics, from highorder skyrmions to the topological Hall effect
AbstractExploring material magnetization led to countless fundamental discoveries and applications, culminating in the field of spintronics. Recently, research effort in this field focused on magnetic skyrmions – topologically robust chiral magnetization textures, capable of storing information and routing spin currents via the topological Hall effect. In this article, we… show more 
8 Feb 2021 • Journal Article • Physical Review Research
Fast universal twoqubit gate for neutral fermionic atoms in optical tweezers
AbstractAn array of ultracold neutral atoms held in optical microtraps is a promising platform for quantum computation. One of the major bottlenecks of this platform is the weak coupling strength between adjacent atoms, which limits the speed of twoqubit gates. Here, we present a method to perform a fast universal √SWAP gate with fermionic atoms that interact through a… show more 
1 Feb 2021 • Journal Article • Annalen Der Physik
FreeElectron Qubits
AbstractFree‐electron interactions with laser‐driven nearfields can quantize the electrons’ energy spectrum and provide control over this quantized degree of freedom. The study proposes to use such interactions to promote free electrons as carriers of quantum information and show how to create a qubit on a free electron, which holds promise for applications in electron microscopy… show more 
27 Jan 2021 • Journal Article • IEEE Nanotechnology Magazine
1.5mm Indium PhosphideBased Quantum Dot Lasers and Optical Amplifiers: The Impact of AtomLike Optical Gain Material for Optoelectronics Devices
AbstractUsing quantum dot (QD) structures as active material for optoelectronics was already in focus before the development of quantum well (QW) lasers and before semiconductor lasers occupied an important place in the market. The big step in reducing laser threshold conditions by substituting bulk gain materials with QWs should find a logical continuation by further reducing… show more 
26 Jan 2021 • Patent
Layered material based quantum light emitting device
AbstractA quantum light emitting device includes a carrier substrate, an insulator, a first semiconductor device, a second semiconductor device, a first contact, and a second contact. The quantum light device includes a carrier substrate comprising silicon and configured with an electrically insulating top surface. The quantum light device also includes an insulator configured… show more 
20 Jan 2021 • Journal Article • Optica
Quantum correlations in electron microscopy
AbstractElectron microscopes provide a powerful platform for exploring physical phenomena with nanoscale resolution, based on the interaction of free electrons with the excitations of a sample such as phonons, excitons, bulk plasmons, and surface plasmons. The interaction usually results in the absorption or emission of such excitations, which can be detected directly through… show more 
22 Dec 2020 • Preprint • arXiv
Ultrafast nondestructive measurement of the quantum state of light using free electrons
AbstractSince the birth of quantum optics, the measurement of quantum states of nonclassical light has been of tremendous importance for advancement in the field. To date, conventional detectors such as photomultipliers, avalanche photodiodes, and superconducting nanowires, all rely at their core on linear excitation of bound electrons with light, posing fundamental restrictions… show more 
7 Dec 2020 • Journal Article • Physical Review B
Selective noise resistant gate
AbstractRealizing individual control on single qubits in a spinbased quantum register is an everincreasing challenge due to the close proximity of the qubits’ resonance frequencies. Current schemes typically suffer from an inherent tradeoff between fidelity and qubits selectivity. Here, we report on a scheme which combines noise protection by dynamical decoupling and magnetic… show more 
3 Dec 2020 • Preprint • arXiv
Security Proof Against Collective Attacks for an Experimentally Feasible SemiQuantum Key Distribution Protocol
AbstractSemiquantum key distribution (SQKD) allows two parties (Alice and Bob) to create a shared secret key, even when one of these parties (say, Alice) is classical. However, most SQKD protocols suffer from severe practical security problems when implemented using photons. The recently developed "Mirror protocol" [Boyer, Katz, Liss, and Mor, Phys. Rev. A 96, 062335 (2017)]… show more 
1 Dec 2020 • Journal Article • Optics & Photonics News
Branched Flow of Light
AbstractBranched flow is a universal wave phenomenon in which waves form channels of enhanced intensity that keep dividing as they propagate, resulting in a beautiful pattern resembling the branches of a tree. First observed for electrons, it can occur for virtually any kind of wave. Recently, we presented the experimental observation of branched flow of light. 
1 Dec 2020 • Journal Article • Optics & Photonics News
Toward Quantum Optics with Free Electrons
AbstractThe weak coupling between free electrons and light remains the limiting factor that has prevented access to versatile electron–photon physics, such as the entanglement of individual photons and electrons. This year, we demonstrated that photonic cavities can increase the coupling strength of electrons and light by more than an order of magnitude. 
30 Nov 2020 • Journal Article • TPNC 2020: Theory and Practice of Natural Computing
Quantum Candies and Quantum Cryptography
AbstractThe field of quantum information is becoming more known to the general public. However, effectively demonstrating the concepts underneath quantum science and technology to the general public can be a challenging job. We investigate, extend, and much expand here “quantum candies” (invented by Jacobs), a pedagogical model for intuitively describing some basic concepts in… show more 
30 Nov 2020 • Journal Article • TPNC 2020: Theory and Practice of Natural Computing
From Practice to Theory: The "Bright Illumination" Attack on Quantum Key Distribution Systems
AbstractThe “Bright Illumination” attack is a practical attack, fully implementable against quantum key distribution systems. In contrast to almost all developments in quantum information processing (for example, Shor’s factorization algorithm, quantum teleportation, BennettBrassard (BB84) quantum key distribution, the “PhotonNumber Splitting” attack, and many other examples)… show more 
4 Nov 2020 • Preprint • arXiv
Super and subradiance by entangled free particles
AbstractWhen multiple quantum emitters radiate, their emission rate may be enhanced or suppressed due to collective interference in a process known as super or subradiance. Such processes are wellknown to occur also in light emission by free charged particles. To date, all experimental and theoretical studies of super and subradiance in these systems involved the classical… show more 
1 Nov 2020 • Preprint • arXiv
Light emission is fundamentally tied to the quantum coherence of the emitting particle
AbstractCoherent emission of light by free charged particles is ubiquitous in many areas of physics and engineering, with the light's properties believed to be successfully captured by classical electromagnetism in all relevant experimental settings. The advent of interactions between light and free quantum matter waves brought about fundamental questions regarding the role of… show more 
27 Oct 2020 • Journal Article • Physical Review X
Observation of a Smooth PolaronMolecule Transition in a Degenerate Fermi Gas
AbstractUnderstanding the behavior of an impurity strongly interacting with a Fermi sea is a longstanding challenge in manybody physics. When the interactions are short ranged, two vastly different ground states exist: a polaron quasiparticle and a molecule dressed by the majority atoms. In the singleimpurity limit, it is predicted that at a critical interaction strength, a… show more 
26 Oct 2020 • Journal Article • Physical Review A
Drivinginduced resonance narrowing in a strongly coupled cavityqubit system
AbstractWe study a system consisting of a superconducting flux qubit strongly coupled to a microwave cavity. Externally applied qubit driving is employed in order to manipulate the spectrum of dressed states. We observe resonance narrowing in the region where the splitting between the two dressed fundamental resonances is tuned to zero. The narrowing in this region of overlapping
… show more 
12 Oct 2020 • Journal Article • Nature Physics
Resonant phasematching between a light wave and a freeelectron wavefunction
AbstractQuantum light–matter interactions of bound electron systems have been studied extensively. By contrast, quantum interactions of free electrons with light have only become accessible in recent years, following the discovery of photoninduced nearfield electron microscopy (PINEM). So far, the fundamental free electron–light interaction in all PINEM experiments has remained… show more 
23 Sep 2020 • Journal Article • Nature Reviews Physics
Light–matter interactions with photonic quasiparticles
AbstractInteractions between light and matter play an instrumental role in spectroscopy, sensing, quantum information processing and lasers. In most of these applications, light is considered in terms of electromagnetic plane waves propagating at the speed of light in vacuum. As a result, light–matter interactions can usually be treated as very weak and captured at the lowest
… show more 
22 Sep 2020 • Journal Article • New Journal of Physics
Subwavelength spin excitations in ultracold gases created by stimulated Raman transitions
AbstractRaman transitions are used in quantum simulations with ultracold atoms for cooling, spectroscopy and creation of artificial gauge fields. Spatial shaping of the Raman fields allows local control of the effective Rabi frequency, which can be mapped to the atomic spin. Evanescent Raman fields are of special interest as they can provide a new degree of control emanating… show more 
14 Sep 2020 • Journal Article • Advances in Physics: X
Continuous measurements for control of superconducting quantum circuits
AbstractDevelopments over the last two decades have opened the path towards quantum technologies in many quantum systems, such as cold atoms, trapped ions, cavityquantum electrodynamics (QED), and circuitQED. However, the fragility of quantum states to the effects of measurement and decoherence still poses one of the greatest challenges in quantum technology. An imperative… show more 
14 Sep 2020 • Journal Article • Nature Communications
The quantumoptical nature of high harmonic generation
AbstractHigh harmonic generation (HHG) is an extremely nonlinear effect generating coherent broadband radiation and pulse durations reaching attosecond timescales. Conventional models of HHG that treat the driving and emitted fields classically are usually very successful but inherently cannot capture the quantumoptical nature of the process. Although prior work considered
… show more 
14 Sep 2020 • Conference Paper • OSA Quantum 2.0 Conference (2020), Paper QM5B.4
Deterministic generation of a clusterstate of indistinguishable entangled photons
AbstractWe use periodic excitation of a semiconductor quantumdotconfined hole to demonstrate gigahertz rate deterministic generation of long strings of entangled indistinguishable photons in a cluster state. The entanglement lasts for 11 consecutive photons. 
28 Aug 2020 • Journal Article • Nanophotonics
Scattering of a single plasmon polariton by multiple atoms for inplane control of light
AbstractWe study the interaction of a single photon in a surface plasmon polariton mode with multiple atoms. We propose a system of two atoms to achieve a tunable scattering from subscattering to superscattering regimes by changing the angle of the incident photon. We also demonstrate a perfect electromagneticallyinduced transparency using two atoms with twolevel structures… show more 
27 Aug 2020 • Journal Article • Journal of Physics: Condensed Matter
HighT c Cooperpair injection in a semiconductorsuperconductor structure
AbstractWe observe Andreev reflection in a YBCOGaN junction through differential conductance spectroscopy. A strong characteristic zerobias peak was observed and persisted up to the critical temperature of the superconductor with a smaller superconducting order parameter Δ ∼ 1 meV. The presence of Andreev reflection with the small Δ in comparison to its value for highT c… show more 
24 Aug 2020 • Journal Article • Nature Nanotechnology
Photonic Rashba effect from quantum emitters mediated by a Berryphase defective photonic crystal
AbstractHeterostructures combining a thin layer of quantum emitters and planar nanostructures enable customtailored photoluminescence in an integrated fashion. Here, we demonstrate a photonic Rashba effect from valley excitons in a WSe_{2} monolayer, which is incorporated into a photonic crystal slab with geometric phase defects, that is, into a Berryphase defective photonic
… show more 
Implications of quantum optics in high harmonic generation
AbstractEffects of extreme nonlinear optics, such as high harmonic generation (HHG), are conventionally modeled with classical electromagnetic fields: both the driving and emitted fields are treated classically. We present the fully quantum electrodynamical theory of extreme nonlinear optics and use it to predict new quantum effects in HHG. The quantum description shows new… show more 
20 Aug 2020 • Journal Article • ACS Photonics
Theory of Shaping Electron Wavepackets with Light
AbstractWe present the quantum theory governing the interaction between short laser pulses and relativistic free electrons and reveal intrinsic conservation laws for such quantum interactions. Through the judicious design of the amplitude and phase of a laser pulse, we propose the complete shaping of the electron temporal wavepacket and energy spectrum. To exemplify the prospects… show more 
13 Aug 2020 • Journal Article • Journal of Magnetic Resonance Open
Electron spin resonance microfluidics with subnanoliter liquid samples
AbstractMicrofluidics is a wellestablished technique to synthesize, process, and analyze small amounts of materials for chemical, biological, medical, and environmental applications. Typically, it involves the use of reagents with a volume smaller than ~ 1 microl—ideally even nano or picoliters. When the sample of interest contains paramagnetic species, it
… show more 
3 Aug 2020 • Conference Paper • CLEO PR 2020: Pacific Rim Conference on Lasers and ElectroOptics
Generation of heralded entangled photon combs at telecom wavelength with rubidium Rydberg atom cavity QED
AbstractWe proposed a protocol to generate entangled photoncomb pairs using rubidium Rydberg atoms inside an optical cavity. Rydberg blockade isolates a single excitation and the heralding enables nondestructive detection of the presence of photonpairs. 
30 Jul 2020 • Conference Paper • Nanoscience and Nanotechnology in Security and Protection against CBRN Threats
Fabrication of Diamond AFM Tips for Quantum Sensing
AbstractDiamond attracts an everincreasing scientific interest not only due to its outstanding properties, but also as host material for the socalled color centers. In particular, the nitrogenvacancy (NV) center is a promising candidate for applications in quantum sensing on a nanoscale. Incorporating such centers in sharp diamond tips, allows the fabrication of a controllable
… show more 
29 Jul 2020 • Journal Article • SciPost Physics
Exponentially long lifetime of universal quasisteady states in topological Floquet pumps
AbstractWe investigate a mechanism to transiently stabilize topological phenomena in longlived quasisteady states of isolated quantum manybody systems driven at low frequencies. We obtain an analytical bound for the lifetime of the quasisteady states which is exponentially large in the inverse driving frequency. Within this lifetime, the quasisteady state is characterized… show more 
20 Jul 2020 • Journal Article • Nature Physics
Implementation of a canonical phase measurement with quantum feedback
AbstractMuch of modern metrology and communication technology encodes information in electromagnetic waves, typically as an amplitude or phase. Although current hardware can perform nearideal measurements of photon number or field amplitude, the ability to perform an ideal phase measurement is still lacking, even in principle. In this work, we implement a singleshot canonical
… show more 
15 Jul 2020 • Journal Article • Physical Review A
Twolevel quantum system as a macroscopic scatterer for ultraconfined twodimensional photonic modes
AbstractWe study the scattering of a single photon in the surface plasmon polariton mode propagating on a twodimensional surface, by a twolevel quantum system in the regime where the photon wavelength becomes comparable or smaller than the size of the electron wave function. In this interesting regime, the scattering spectral signature becomes highly dependent on the shape… show more 
14 Jul 2020 • Journal Article • Physical Review Letters
P T Symmetric Topological EdgeGain Effect
AbstractWe demonstrate a nonHermitian topological effect that is characterized by having complex eigenvalues only in the edge states of a topological material, despite the fact that the material is completely uniform. Such an effect can be constructed in any topological structure formed by two gapped subsystems, e.g., a quantum spinHall system, with a suitable nonHermitian… show more 
6 Jul 2020 • Journal Article • Physical Review Applied
SingleExposure Absorption Imaging of Ultracold Atoms Using Deep Learning
AbstractAbsorption imaging is the most common probing technique in experiments with ultracold atoms. The standard procedure involves the division of two frames acquired at successive exposures, one with the atomic absorption signal and one without. A wellknown problem is the presence of residual structured noise in the final image, due to small differences between the imaging… show more 
6 Jun 2020 • Journal Article • Entropy
Quantum Communication  Celebrating the Silver Jubilee of Teleportation
AbstractIn 1993, Charles H. Bennett, Gilles Brassard, Claude Crépeau, Richard Jozsa, Asher Peres, and William K. Wootters published their seminal paper presenting quantum teleportation, titled “Teleporting an unknown quantum state via dual classical and Einstein–Podolsky–Rosen channels” [1]. Their paper presents and answers the question “Can we transmit an unknown quantum state… show more 
3 Jun 2020 • Journal Article • Physical Review B
Towards supersensitive optical phase measurement using a deterministic source of entangled multiphoton states
AbstractPrecision measurements of optical phases have many applications in science and technology. Entangled multiphoton states have been suggested for performing such measurements with precision that significantly surpasses the shotnoise limit. Until recently, such states have been generated mainly using spontaneous parametric downconversion—a process which is intrinsically… show more 
3 Jun 2020 • Journal Article • arXiv
Coherent Interaction Between Free Electrons and a Photonic Cavity
AbstractAdvances in the research of interactions between ultrafast free electrons and light have introduced a previously unknown kind of quantum matter, quantum freeelectron wavepackets. So far, studies of the interactions of cavityconfined light with quantum matter have focused on bound electron systems, such as atoms, quantum dots and quantum circuits, which are considerably… show more 
25 May 2020 • Journal Article • Nature Physics
Tunable bandgap renormalization by nonlocal ultrastrong coupling in nanophotonics
AbstractIn quantum optics, great effort is being invested in enhancing the interaction of quantum emitters with light. The different approaches include increasing the number of emitters, the laser intensity or the local photonic density of states at the location of an atomlike localized emitter. In contrast, solidstate extended emitters hold an unappreciated promise of vastly… show more 
15 May 2020 • Conference Paper • CLEO: Applications and Technology 2020
Design and Fundamental Limits of Nearfield MagneticForce Scanning Microscopy via the NoCloning Theorem
AbstractWe analyze nearfield measurements of magnetic fields originating from quantum sources and measured by quantum probes. We show that cloninginspired techniques reveal optimal measurement schemes and new universal precision bounds for nearfield detectors. 
15 May 2020 • Conference Paper • 2020 Conference on Lasers and ElectroOptics (CLEO)
Quantum Walk with Coherent Uncertainty in ElectronLaser Interaction
AbstractWe show that pulsed laserdriven free electrons undergo quantum walk with coherent uncertainty in the electron energy levels, characterized by their spread. We study this quantum walk experimentally and develop its analytic theory. 
15 May 2020 • Conference Paper • CLEO: QELS_Fundamental Science 2020
Free Electron Cavity Quantum Electrodynamics in an Ultrafast Electron Microscope
AbstractWe observe an increased interaction strength and time between quantum electron wavepackets and laser pulses due to the large Qfactor of a photonic crystal slab, promoting the integration of freeelectron emitters into cavity quantum electrodynamics. 
15 May 2020 • Conference Paper • Conference on Lasers and Electro Optics
Topologically Protected PathEntangled Photonic States
AbstractWe report our experimental results on topologically protected pathentangled photonic states using dimer chains in silicon photonics. These results highlight the potential of the lattice topology to protect photonic quantum information. 
1 May 2020 • Journal Article • Nano Letters
Novel Ultra Localized and Dense Nitrogen DeltaDoping in Diamond for Advanced Quantum Sensing
AbstractWe introduce and demonstrate a new approach for nitrogenvacancy (NV) patterning in diamond, achieving a deterministic, nanometerthin, and dense deltadoped layer of negatively charged NV centers in diamond. We employed a pure nitridation stage using microwave plasma and a subsequent in situ diamond overgrowth. We present the highest reported nitrogen concentration in… show more 
27 Apr 2020 • Journal Article • Nature Nanotechnology
Probing nanoscale fluctuation of ferromagnetic metaatoms with a stochastic photonic spin Hall effect
AbstractThe photonic spin Hall effect, a deep subdiffractionlimited shift between the opposite spin components of light, emerges when light undergoes an evolution of polarization or trajectory that induces the geometric phase. Here, we study a stochastic photonic spin Hall effect arising from spacevariant Berry–Zak phases, which are generated by disordered magnetooptical
… show more 
12 Mar 2020 • Journal Article • New Journal of Physics
Learning the dynamics of open quantum systems from their steady states
AbstractRecent works have shown that generic local Hamiltonians can be efficiently inferred from local measurements performed on their eigenstates or thermal states. Realistic quantum systems are often affected by dissipation and decoherence due to coupling to an external environment. This raises the question whether the steady states of such open quantum systems contain… show more
22 Nov 2021