Latest in physics.optics

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Comment on "Nonreciprocal cavities and the time-bandwidth limit"Jun 13 2019In their paper in Optica 6, 104 (2019), Mann et al. claim that time-invariant nonreciprocal cavities cannot overcome the time-bandwidth limit, based on their numerical analysis and temporal coupled-mode theory of an example structure. In this comment, ... More
Active meta-optics and nanophotonics with halide perovskitesJun 13 2019Meta-optics based on optically resonant all-dielectric structures is a rapidly developing research area driven by its potential applications for low-loss efficient metadevices. Active, light-emitting subwavelengh nanostructures and metasurfaces are of ... More
Stopped and stationary light at the single-photon level inside a hollow-core fiberJun 13 2019An experimental platform operating at the level of individual quanta is a key requirement for quantum information processing. We report on narrowband light storage and retrieval as well as stationary light for weak coherent light pulses down to the single-photon ... More
Cooperative spontaneous emission via renormalization approach: Classical versus semi-classical effectsJun 13 2019We address the many-atom emission of a dilute cloud of two-level atoms through a renormalized perturbation theory. An analytical solution for the truncated coupled-dipole equations is derived, which contains an effective spectrum associated to the initial ... More
Direct optical excitation of an NV center via a nanofiber Bragg-cavity: A theoretical simulationJun 13 2019Direct optical excitation of a nitrogen-vacancy (NV) center in nanodiamond by light via a nanofiber is of interest for all-fiber-integrated quantum applications. However, the background light induced by the excitation light via the nanofiber is problematic ... More
Full spatiotemporal control of laser-excited periodic surface deformationsJun 13 2019We demonstrate full control of acoustic and thermal periodic deformations at solid surfaces down to sub-nanosecond time scales and few-micrometer length scales via independent variation of the temporal and spatial phase of two optical transient grating ... More
On the overall polarisation properties of full Poincaré beamsJun 12 2019We analyse the polarisation properties of full Poincar\'e beams. We consider different configurations, such as Laguerre-Poincar\'e, Bessel-Poincar\'e, and Lambert-Poincar\'e beams. The former is the original Poincar\'e beam produced by a collinear superposition ... More
Overlapping domains for topology optimization of large-area metasurfacesJun 12 2019We introduce an overlapping-domain approach to large-area metasurface design, in which each simulated domain consists of a unit cell and overlapping regions from the neighboring cells plus PML absorbers. We show that our approach generates greatly improved ... More
Skymionic beamsJun 12 2019Vector vortex beams possess a topological property that derives both from the spatially varying amplitude of the field and also from its varying polarization. This property arises as a consequence of the natural Skyrmionic nature of such beams and is ... More
Photonic crystal spatial filtering in broad aperture diode laserJun 12 2019The emission from broad aperture semiconductor lasers suffers from low spatial quality of the emitted beams. Due to the highly compact character of such systems the use of a conventional intra-cavity spatial filter is problematic. We demonstrate, that ... More
Vorticity and the birth of optical vorticesJun 12 2019We exploit the vorticity, familiar from fluid mechanics and the theory of superfluids, as a tool to track the birth and subsequent development of optical vortices at a spiral phase plate.
Electromagnetism at finite temperature: a density operator approachJun 12 2019In order to analyse classical electromagnetism in a medium at finite temperature, we introduce "optical density operator," and reformulate Maxwell equations with the operator, starting from the Dirac-equation-like formulation of electromagnetism. The ... More
Energy transfer and interference by collective electromagnetic couplingJun 12 2019The physics of collective optical response of molecular assemblies, pioneered by Dicke in 1954, has long been at the center of theoretical and experimental scrutiny. The influence of the environment on such phenomena is also of great interest due to various ... More
Generating single longitudinal mode entangled photons in telecom band via a submillimeter monolithic cavityJun 12 2019A high-quality, compact, and narrow-bandwidth entangled photon source (EPS) is indispensable for realization of many quantum communication protocols. Usually, a free space cavity containing a nonlinear crystal is used to generate a narrow bandwidth EPS ... More
High-efficiency thermophotovoltaic system that employs an emitter based on a silicon rod-type photonic crystalJun 12 2019Thermophotovoltaic systems in principle enable utilization of heat that is usually regarded as wasted energy. However, the wavelength selectivity of the thermal emitter required for high efficiencies is rather difficult to control with conventional designs. ... More
Crown-structured optical harmonicsJun 12 2019At levels of laser intensity below threshold for multiphoton ionization, the parametric generation of optical harmonics in gases and other isotropic media is subject to selection rules with origins in angular momentum conservation. The recently developed ... More
Fresnel diffraction of cylindrical and spherical wavefronts from a phase plateJun 12 2019In the last two decades, Fresnel diffraction (FD) of a plane wave from phase steps has been systematically studied and applied for precise measurements of light wavelength, and height and refractive index of the step. In this study we formulate FD of ... More
Adiabatic frequency conversion: it is all about group velocityJun 11 2019We investigate adiabatic frequency conversion using epsilon near zero (ENZ) materials and show that while the maximum frequency conversion for a given change of permittivity does not exhibit increase in the vicinity of {\epsilon}=0 condition. However, ... More
Snapshot projection optical tomographyJun 11 2019We present a new plenoptic microscopy configuration consisting of an objective lens and a micro-lens array (MLA), which is used as a tube lens. The new system that we named as snapshot projection optical tomography (SPOT) can directly record the projection ... More
Quantum, Nonlocal Aberration CancellationJun 11 2019Phase distortions, or aberrations, can negatively influence the performance of an optical imaging system. Through the use of position-momentum entangled photons, we nonlocally correct for aberrations in one photon's optical path by intentionally introducing ... More
Biomimetic Polymer Film with Brilliant Brightness Using a One-Step Water Vapor-Induced Phase Separation MethodJun 11 2019The scales of the white Cyphochilus beetles are endowed with unusual whiteness arising from the exceptional scattering efficiency of their disordered ultrastructure optimized through millions of years of evolution. Here, a simple, one-step method based ... More
Semiparametric estimation for incoherent optical imagingJun 11 2019The theory of semiparametric estimation offers an elegant way to compute the Cram\'er-Rao bound for a parameter of interest in the midst of infinitely many nuisance parameters. Here I apply the theory to the problem of moment estimation for incoherent ... More
Self-induced transparency mode-locking in a Ti:sapphire laser with an intracavity rubidium cellJun 11 2019In a Ti:Sa laser with an absorbing with Rb vapor cell stable self-starting passive mode-locking is demonstrated. We show that the mode-locking appears due to self-induced transparency (SIT) in the Rb cell, that is, the pulse in the Rb cell is a 2pi SIT ... More
A quantum emitter coated with graphene interacting in the strong coupling regimeJun 11 2019Jun 12 2019We investigate the optical response of a graphene spherical shell which has a semi-conducting material core through their absorption spectrum. The semi-conducting material is described by a Lorenztian expression, which approximates the optical responce ... More
A quantum emitter coated with graphene interacting in the strong coupling regimeJun 11 2019We investigate the optical response of a graphene spherical shell which has a semi-conducting material core through their absorption spectrum. The semi-conducting material is described by a Lorenztian expression, which approximates the optical responce ... More
Interference-type plasmonic polarizers and generalized law of MalusJun 11 2019The conventional linear polarizer only allows the electric component parallel to the polarizer axis to pass through whereas prohibits the vertical component. We propose that a specially-designed single-layer plasmonic polarizer can couple both parallel ... More
Adaptive optics benefit for quantum key distribution uplink from ground to a satelliteJun 10 2019For quantum communications, the use of Earth-orbiting satellites to extend distances has gained significant attention in recent years, exemplified in particular by the launch of the Micius satellite in 2016. The performance of applied protocols such as ... More
Universal driving protocol for symmetry-protected Floquet topological phasesJun 10 2019Universal driving protocol for symmetry-protected Floquet topological phasesWe propose a universal driving protocol for the realization of symmetry-protected topological phases in $2+1$ dimensional Floquet systems. Our proposal is based on the theoretical ... More
Nonlinear ultrafast fiber amplifiers beyond the gain-narrowing limitJun 10 2019Ultrafast lasers are becoming increasingly widespread in science and industry alike. Fiber-based ultrafast laser sources are especially attractive because of their compactness, alignment-free setups, and potentially low costs. However, confining short ... More
A Simple Coupled-Bloch-Mode Approach To Study Active Photonic Crystal Waveguides and LasersJun 10 2019By applying a coupled-Bloch-mode approach, we have derived a simple expression for the transmission properties of photonic crystal (PhC) line-defect waveguides with a complex refractive index perturbation. We have provided physical insights on the coupling ... More
Exceptional points and their coalescence of PT-symmetric interface states in photonic crystalsJun 10 2019The existence of surface electromagnetic waves in the dielectric-metal interface is due to the sign change of real parts of permittivity across the interface. In this work, we demonstrate that the interface constructed by two semi-infinite photonic crystals ... More
Two-dimensional non-Hermitian topological phases induced by asymmetric hopping in a one-dimensional superlatticeJun 10 2019Non-Hermitian systems can host novel topological states with novel topological invariants and bulk-edge correspondences that are distinct from conventional Hermitian systems. Here we show that two unique classes of non-Hermitian 2D topological phases, ... More
Noninvasive super-resolution imaging through scattering mediaJun 10 2019Super-resolution imaging with advanced optical systems has been revolutionizing technical analysis in various fields from biological to physical sciences. However, many objects are hidden by strongly scattering media such as biological tissues or wall ... More
Room Temperature Initialisation and Readout of Intrinsic Spin Defects in a Van der Waals CrystalJun 10 2019Optically addressable spins in widebandgap semiconductors have become one of the most prominent platforms for exploring fundamental quantum phenomena. While several candidates in 3D crystals including diamond and silicon carbide have been extensively ... More
Single-photon interferometry and spectroscopy with two laser frequency combsJun 09 2019We demonstrate single-photon time-domain interference in a new realm. We observe interferences in the photon counting statistics with two separate mode-locked femtosecond lasers of slightly different repetition frequencies, each emitting a comb of evenly ... More
Effective Local Permittivity Model for Non-Local Wire MediaJun 09 2019A local permittivity model is proposed to accurately characterize spatial dispersion in non-local wire-medium (WM) structures with arbitrary terminations. A closed-form expression for the local thickness-dependent permittivity is derived for a general ... More
An Equivalent ABCD-Matrix Formalism for Non-Local Wire Media with Arbitrary TerminationsJun 09 2019A simple analytical model based on the transmission-matrix approach is proposed for equivalent wire-medium (WM) interfaces. The obtained ABCD matrices for equivalent interfaces capture the non-local effects due to the evanescent transverse magnetic (TM) ... More
Coupled Bloch-Wave Analysis of Active PhC Waveguides and CavitiesJun 09 2019A coupled Bloch-wave approach is employed to analyze active photonic-crystal (PhC) waveguides and cavities. Gain couples the otherwise independent counter-propagating Bloch modes. This coupling is shown to limit the maximum attainable slow-light enhancement ... More
Phenomenology of complex structured light in turbulent airJun 09 2019The study of light propagation can be traced back 24 centuries, to the ancient Chinese philosopher Mo Zi, and it has since been a cornerstone of progress in physics and technology. More recently, advances in control and shaping of light has created a ... More
Generation and Characterization of Tailored MIR Waveforms for Steering Molecular DynamicsJun 08 2019The dream of physico-chemists to control molecular reactions with light beyond electronic excitations pushes the development of laser pulse shaping capabilities in the mid-infrared (MIR) spectral range. Here, we present a compact optical parametric amplifier ... More
Multichannel remote polarization control enabled by nanostructured Liquid Crystalline NetworksJun 08 2019In this article we demonstrate that a grating fabricated through nanoscale volumetric crosslinking of a liquid crystalline polymer enables remote polarization control over the diffracted channels. This functionality is a consequence of the responsivity ... More
Class-specific Differential Detection in Diffractive Optical Neural Networks Improves Inference AccuracyJun 08 2019Diffractive deep neural networks have been introduced earlier as an optical machine learning framework that uses task-specific diffractive surfaces designed by deep learning to all-optically perform inference, achieving promising performance for object ... More
A Novel Modeling Approach for All-Dielectric Metasurfaces Using Deep Neural NetworksJun 08 2019Metasurfaces have become a promising means for manipulating optical wavefronts in flat and high-performance optical devices. Conventional metasurface device design relies on trial-and-error methods to obtain target electromagnetic (EM) response, an approach ... More
Synthesis and Observation of Non-Abelian Gauge Fields in Real SpaceJun 08 2019Gauge fields, real or synthetic, are crucial for understanding and manipulation of physical systems. The associated geometric phases can be measured, for example, from the Aharonov--Bohm interference. So far, real-space realizations of gauge fields have ... More
Indirect but Efficient: Laser-Excited Electrons Can Drive Ultrafast Polarization Switching in Ferroelectric MaterialsJun 07 2019To enhance the efficiency of next-generation ferroelectric (FE) electronic devices, new techniques for controlling ferroelectric polarization switching are required. While most prior studies have attempted to induce polarization switching via the excitation ... More
Sum-frequency generation through a unique Feynman diagram formalism: the case of bipartite organic/inorganic complexesJun 07 2019In quantum electrodynamics, optical processes are theoretically described by double-sided Feynman diagrams. This formalism is powerful in the case of molecules but proves inappropriate to account for light-matter interactions within complex hybrid systems ... More
Spin-alignment noise in atomic vaporJun 07 2019In the conventional spin noise spectroscopy, the probe laser light monitors fluctuations of the spin orientation of a paramagnet revealed as fluctuations of its gyrotropy, i.e., circular birefringence. For spins larger than 1/2, there exists spin arrangement ... More
Towards Arbitrary Control of Lattice Interactions in Nonequilibrium CondensatesJun 07 2019There is a growing interest in investigating new states of matter using out-of-equilibrium lattice spin models in two dimensions. However, a control of pairwise interactions in such systems has been elusive as due to their nonequilibrium nature they maintain ... More
Non-adiabatic transitions through exceptional points in the band structure of a PT-symmetric latticeJun 07 2019Exceptional points, at which two or more eigenfunctions of a Hamiltonian coalesce, occur in non-Hermitian systems and lead to surprising physical effects. In particular, the behaviour of a system under parameter variation can differ significantly from ... More
Standardized spectral and radiometric calibration of consumer camerasJun 07 2019Consumer cameras, particularly onboard smartphones and UAVs, are now commonly used as scientific instruments. However, their data processing pipelines are not optimized for quantitative radiometry and their calibration is more complex than that of scientific ... More
Tunable dual-comb from an all-polarization-maintaining single-cavity dual-color Yb:fiber laserJun 07 2019We demonstrate dual-comb generation from an all-polarization-maintaining dual-color ytterbium (Yb) fiber laser. Two pulse trains with center wavelengths at 1030 nm and 1060 nm respectively are generated within the same laser cavity with a repetition rate ... More
Zeeman-tunable Modulation Transfer SpectroscopyJun 07 2019Active frequency stabilization of a laser to an atomic or molecular resonance underpins many modern-day AMO physics experiments. With a flat background and high signal-to-noise ratio, modulation transfer spectroscopy (MTS) offers an accurate and stable ... More
Achievability of Quantum Regime in Optomechanics of Electromagnetically Levitated Nanoparticles: Inclusion of Gradient Force FluctuationsJun 07 2019Counterintuitively, experiments show that an electromagnetically levitated particle escapes from its trap when the ambient pressure is reduced below a certain level even if the particle's motion is cooled by a resonator-based or feedback-based mechanism. ... More
Photonic quadrupole topological phases in zero-dimensional cavity with synthetic dimensionsJun 07 2019Quadrupole topological insulator, which supports robust corner states, has been recently demonstrated in two-dimensional (2D) spatial lattices. Here, we design the first photonic quadrupole topological insulator in fully synthetic spaces with the utilization ... More
Dicke subradiance and thermal decoherenceJun 07 2019Subradiance is the cooperative inhibition of the radiation by several emitters coupled to the same electromagnetic modes. It has been predicted by Dicke in 1954 and only recently observed in cold atomic vapors. Here we address the question to what extend ... More
Quantum random number generation by coherent detection of phase noiseJun 06 2019We demonstrate a quantum random number generator based on the random nature of the phase difference between two independent laser sources. The speed of random bit generation is determined by the photodetector bandwidth and the linewidth of the lasers ... More
Exact Potential Energy Surface for Molecules in CavitiesJun 06 2019We find and analyze the exact time-dependent potential energy surface driving the proton motion for a model of cavity-induced suppression of proton-coupled electron-transfer. We show how, in contrast to the polaritonic surfaces, its features directly ... More
On the physical (im)possibility of lightsabersJun 06 2019In this paper, we use a science fiction theme (i.e. the iconic lightsaber from the Star Wars universe) as a pedagogical tool to introduce aspects of nonlinear electrodynamics due to the quantum vacuum to an audience with an undergraduate physics background. ... More
Enantioselective manipulation of chiral nanoparticles using optical tweezersJun 06 2019We put forward a twofold enantioselective method for chiral nanoparticles using optical tweezers. First, we demonstrate that the optical trapping force in a typical, realistic optical tweezing setup with circularly-polarized trapping beams are sensitive ... More
Coherence and Interaction in confined room-temperature polariton condensates with Frenkel excitonsJun 06 2019The strong light-matter coupling of a microcavity mode to tightly bound Frenkel excitons in organic materials emerged as a versatile, room-temperature compatible platform to study nonlinear many-particle physics and bosonic condensation. However, various ... More
Observation of incoherently coupled dark-bright vector solitons in single-mode fibersJun 06 2019We report experimental observation of incoherently coupled dark-bright vector solitons in single-mode fibers. Properties of the vector solitons agree well with those predicted by the respective systems of incoherently coupled nonlinear Schroedinger equations. ... More
Topological Ring-Cavity Laser Formed by Honeycomb Photonic CrystalsJun 06 2019We propose a topological ring-cavity (TRC) laser where the topological cavity modes circulating along the interface between two honeycomb-type dielectric photonic crystals (PhCs) distinct in topology are exploited for lasing. We show theoretically that, ... More
Evolution of the resonances of two parallel dielectric cylinders with distance between themJun 06 2019We study behavior of resonant modes under change of the distance between two parallel dielectric cylinders. The processes of mutual scattering of Mie resonant modes by cylinders result in an interaction between the cylinders which lifts a degeneracy of ... More
Improved second harmonic performance in periodically poled LNOI waveguides through engineering of lateral leakageJun 06 2019In this contribution we investigate the impact of lateral leakage for linear and nonlinear optical waveguides in lithium niobate on insulator (LNOI). Silicon nitride (SiN) loaded and direct patterned lithium niobate cross-sections are investigated. We ... More
Phase relations in a photonic 4-dimensional Hadamard gate - a non-polarizing beamsplitterJun 05 2019Beamsplitter is often given as a matrix acting on a vector with two basis states. This might be comprehensive for a scalar field but certainly insufficient in case of photons which are vector fields. In this paper we discuss theoretical grounds to accurately ... More
Spin-Wave Optical Elements: Towards Spin-Wave Fourier OpticsJun 05 2019We perform micromagnetic simulations to investigate the propagation of spin-wave beams through spin-wave optical elements. Despite spin-wave propagation in magnetic media being strongly anisotropic, we use axicons to excite spinwave Bessel-Gaussian beams ... More
Calibration of free-space and fiber-coupled single-photon detectorsJun 05 2019We measure the detection efficiency of single-photon detectors at wavelengths near 851 nm and 1533.6 nm. We investigate the spatial uniformity of one free-space-coupled single-photon avalanche diode and present a comparison between fusion-spliced and ... More
Generation and dynamics of solitonic pulses due to pump amplitude modulation at normal group velocity dispersionJun 05 2019We studied generation and dynamics of solitonic pulses, platicons, at normal group velocity dispersion due to the pump amplitude modulation. We proposed, that if the required frequency of amplitude modulation is too large for available modulators, it ... More
Optical waveguiding by atomic entanglement in multilevel atom arraysJun 05 2019The optical properties of sub-wavelength arrays of atoms or other quantum emitters have attracted significant interest recently. For example, the strong constructive or destructive interference of emitted light enables arrays to function as nearly perfect ... More
Readout of fluorescence functional signals through highly scattering tissueJun 05 2019Fluorescence is a powerful mean to probe information processing in the mammalian brain. However, neuronal tissues are highly heterogeneous and thus opaque to light. A wide set of non-invasive or invasive techniques for scattered light rejection, optical ... More
Two-photon Quantum Interference and Entanglement at 2 μmJun 05 2019Quantum-enhanced optical systems operating within the 2 {\mu}m spectral region have the potential to revolutionise emerging applications in communications, sensing and metrology. However, to date, sources of entangled photons have been realised mainly ... More
Unconventional Optical Response in Engineered Au-Ag NanostructuresJun 05 2019This article describes the optical properties of nanostructures composed of silver particles embedded into a gold matrix. In previous studies these materials were shown to exhibit temperature dependent transitions to a highly conductive and strongly diamagnetic ... More
Resolving starlight: a quantum perspectiveJun 05 2019The wave-particle duality of light introduces two fundamental problems to imaging, namely, the diffraction limit and the photon shot noise. Quantum information theory can tackle them both in one holistic formalism: model the light as a quantum object, ... More
Optomechanical suspended waveguide for broadband phase modulation with frequency memory effectJun 05 2019Whether it is for transmitting information or for controlling intensity, light modulation is among the essential functions commonly used in complex optical systems. In integrated optics, modulation principles usually include the use of electro-optical ... More
Multimode collective scattering of light in free space by a cold atomic gasJun 05 2019We have studied collective recoil lasing by a cold atomic gas, scattering photons from an incident laser into many radiation modes in free space. The model consists of a system of classical equations for the atomic motion of N atoms, where the radiation ... More
Temperature Measurement in Plasmonic Nanoapertures used for Optical TrappingJun 05 2019Plasmonic nanoapertures generate strong field gradients enabling efficient optical trapping of nano-objects. However, because the infrared laser used for trapping is also partly absorbed into the metal leading to Joule heating, plasmonic nano-optical ... More
Modal analysis for nanoplasmonics with nonlocal material propertiesJun 05 2019Plasmonic devices with feature sizes of few nanometers exhibit effects which can be described by the nonlocal hydrodynamic Drude model. We demonstrate how to exploit contour integral methods for computing eigenfrequencies and resonant states of such systems. ... More
Real-time inteferometric quantum random number generation on chipJun 05 2019We demonstrate on-chip quantum random number generation at high data rates using the random phases of gain-switched laser pulses. Interference of the gain-switched pulses produced by two independent semiconductor lasers is performed on a photonic integrated ... More
Design of Dual-band Graphene-Based Absorbers by Exciting Graphene Plasmon Polaritons: Circuit Model AnalysisJun 05 2019This article presents designing two dual-band absorbers based on graphene metasurfaces for terahertz frequencies. The absorbers are composed of one- and two-dimensional (2D) arrays of ribbons and disks deposited on a dielectric film terminated by a metallic ... More
Surface polaritonic solitons and breathers in a planar plasmonic waveguide structure via electromagnetically induced transparencyJun 05 2019We propose a scheme for the coupler-free excitation of surface polaritonic solitons and breathers in a planar plasmonic waveguide structure comprising of a transparent layer, a metal layer and a layer of three-level lambda-type atomic medium. In the proposed ... More
Orbital angular momentum transfer via spontaneously generated coherenceJun 05 2019We study the orbital angular momentum (OAM) transfer from a weak Laguerre-Gaussian (LG) field to a weak plane-wave in two closed-loop three-level $V$-type atomic systems. In the first scheme, the atomic system has two non-degenerate upper levels which ... More
Multimode waveguide crossing based on square Maxwell's fisheye lensJun 05 2019Mode-division multiplexing (MDM) is an emerging large-capacity data communication technology utilizing orthogonal guiding modes as independent data streams. One of the challenges of multimode waveguide routing in MDM systems is decreasing the mode leakage ... More
Accurate phase retrieval of complex point spread functions with deep residual neural networksJun 04 2019Phase retrieval, i.e. the reconstruction of phase information from intensity information, is a central problem in many optical systems. Here, we demonstrate that a deep residual neural net is able to quickly and accurately perform this task for arbitrary ... More
Complete multipolar description of reflection and transmission across a metasurface for perfect absorption of lightJun 04 2019Relating the electromagnetic scattering and absorption properties of an individual particle to the reflection and transmission coefficients of a two-dimensional material composed of these particles is a crucial concept that has driven both fundamental ... More
Strong optical coupling combines isolated scatterers into dimerJun 04 2019We analyze the transition between different coupling regimes of two dielectric rods, which occurs at a critical distance between them. The hallmark of strong coupling regime is the peak splitting effect observed in spectra. Here we comprehensively evaluate ... More
Advances in Quantum CryptographyJun 04 2019Quantum cryptography is arguably the fastest growing area in quantum information science. Novel theoretical protocols are designed on a regular basis, security proofs are constantly improving, and experiments are gradually moving from proof-of-principle ... More
Geometry and Perturbative Sensitivity of non-Smooth Caustics of the Helmholtz EquationJun 04 2019The geometry of non-smooth $A_{n>2}$ caustics in solutions of the Helmholtz equation is analyzed using a Fock-Schwinger proper-time formulation. In this description, $A_3$ or cusp caustics are intimately related to poles of a quantity called the einbein ... More
Non-invasive light focusing in scattering media using speckle variance optimizationJun 04 2019Optical imaging deep inside scattering media remains a fundamental problem in bio-imaging. While wavefront shaping has been shown to allow focusing of coherent light at depth, achieving it non-invasively remains a challenge. Various feedback mechanisms, ... More
All-optical pulse power editing technique applied to controllable production of the pulse dynamic patterns in fiber lasersJun 04 2019A simple all-optical pulse power editing technique based on the combination of spectral filtering, pulse amplification, and chirped pulse broadening has been reported. The all-optical pulse power editing technique can send pulses of different peak powers ... More
Simple precision measurements of optical beam sizesJun 04 2019We present a simple precision-method to quickly and accurately measure the diameters of Gaussian beams, Airy spots, and central peak of Bessel beams ranging from the sub-millimeter to many centimeters without specialized equipment. Simply moving a wire ... More
Efficient Broadband Terahertz Generation from Organic Crystal BNA Using Near Infrared PumpJun 04 2019We are reporting on terahertz generation from organic crystal BNA using a 1.15 to 1.55 um near infrared pump. We observed a very large emission spectrum extending up to 7 THz, compared to 2.5 THz from Ti:Sa pump in previous reports. The maximum optical-to-THz ... More
Dispersion forces in inhomogeneous planarly layered media: A one-dimensional model for effective polarisabilitiesJun 04 2019Dispersion forces such as van der Waals forces between two microscopic particles, the Casimir--Polder forces between a particle and a macroscopic object or the Casimir force between two dielectric objects are well studied in vacuum. However, in realistic ... More
Thesis: Experimental exploration of gold semi-continuous films in the near- and far-fieldJun 04 2019Metallic nanostructures can support so-called plasma oscillations (plasmons). Plasmons allow for the concentration of the energy from light, down to sizes well below the conventional diffraction limit known from optics. Plasmonics thus allows for a plethora ... More
Packaged photonic chip-based soliton microcomb using an ultralow-noise laserJun 04 2019Photonic chip-based soliton microcombs have shown rapid progress and have already been used in many system-level applications, including coherent communications, astrophysical spectrometer calibration and ultrafast ranging. While there has been substantial ... More
Field ionization rate for PIC codesJun 04 2019An improved formula is proposed for field ionization rate covering tunnel and barrier suppression regime. In contrast to the previous formula obtained recently in [I. Yu. Kostyukov and A. A. Golovanov, Phys. Rev. A 98, 043407 (2018)], it more accurately ... More
Partial temporal coherence effects on the resolution of optical gratingsJun 04 2019We generalize the notion of the Franhoufer diffraction of temporal coherent light from a single slit to the case of arbitrary N-slits. New (a general) numerical method is developed for simulation of diffraction pattern of gratings which is also used to ... More
Bruggeman Approach for Isotropic Chiral Mixtures RevisitedJun 03 2019Two interpretations of the Bruggeman approach for the homogenization of isotropic chiral mixtures are shown to lead to different results. Whereas the standard interpretation is shown to yield the average-polarizability-density approach, a recent interpretation ... More
Topological states at exceptional pointsJun 03 2019We consider an N-level non-Hermitian Hamiltonian with an exceptional point of order N. We define adiabatic equivalence in such systems and explore topological phase. We show that the topological exceptional states appear at the interface of topologically ... More
Topological states at exceptional pointsJun 03 2019Jun 05 2019We consider an N-level non-Hermitian Hamiltonian with an exceptional point of order N. We define adiabatic equivalence in such systems and explore topological phase. We show that the topological exceptional states appear at the interface of topologically ... More
Non-Hermitian phase transition and eigenstate localization induced by asymmetric couplingJun 03 2019We investigate a uniformly coupled non-Hermitian system with asymmetric coupling amplitude. The asymmetric coupling equals to a symmetric coupling threaded by an imaginary gauge field. In a closed configuration, the imaginary gauge field leads to an imaginary ... More