Latest in physics.optics

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Near-Field Scanning Microwave Microscopy in the Single Photon RegimeFeb 21 2019The microwave properties of nano-scale structures are important in a wide variety of applications in quantum technology. Here we describe a low-power cryogenic near-field scanning microwave microscope (NSMM) which maintains nano-scale dielectric contrast ... More
Phase memory preserving harmonics from abruptly autofocusing beamsFeb 21 2019We demonstrate both theoretically and experimentally that the harmonics from abruptly auto-focusing ring-Airy beams present a surprising property, they preserve the phase distribution of the fundamental beam. Consequently, this "phase memory" inherits ... More
Chip-based frequency combs sources for optical coherence tomographyFeb 20 2019The Optical coherence tomography (OCT) is a powerful interferometric imaging technique widely used in medical fields such as ophthalmology, cardiology and dermatology, for which footprint and cost are becoming increasingly important. Here we present a ... More
Single-shot measurement of space varying polarization state of light through interferometric quantification of geometric phaseFeb 20 2019Light beam carrying spatially varying state of polarization generates space varying Pancharatnam-Berry geometric phase while propagating through a homogenous anisotropic medium. We show that determination of such space varying geometric phase provides ... More
Nanostructuring of LNOI for efficient edge couplingFeb 20 2019We present the design, fabrication and characterization of LNOI fiber-to-chip inverse tapers for efficient edge coupling. The etching characteristics of various LNOI crystal cuts are investigated for the realization of butt-coupling devices. We experimentally ... More
Brewster quasi bound states in the continuum in all-dielectric metasurfaces from single magnetic-dipole resonance meta-atomsFeb 19 2019Bound states in the continuum (BICs) are ubiquitous in many areas of physics, attracting especial interest for their ability to confine waves with infinite lifetimes. Metasurfaces provide a suitable platform to realize them in photonics; such BICs are ... More
Fundamentals of cathodoluminescence in a STEM: The impact of sample geometry and electron beam energy on light emission of semiconductorsFeb 19 2019Cathodoluminescence has attracted interest in scanning transmission electron microscopy since the advent of commercial available detection systems with high efficiency, like the Gatan Vulcan or the Attolight M\"onch system. In this work we discuss light ... More
Spatial modulation of the electromagnetic energy transfer by excitation of graphene waveguide surface plasmonsFeb 19 2019We theoretically study the electromagnetic energy transfer between donor and acceptor molecules near a graphene waveguide. The surface plasmons (SPs) supported by the structure provide decay channels which lead to an improvement in the energy transfer ... More
946-nm Nd:YAG digital-locked laser at $1.1\times10^{-16}$ in 1 s and transfer-locked to a cryogenic silicon cavityFeb 19 2019We present a Nd:YAG ultra-stable laser system operating at 946 nm and demonstrate a fractional frequency instability of $1.1\times10^{-16}$ at 1 s by pre-stabilizing it to a 30 cm-long ULE cavity at room temperature. All key analog components have been ... More
Soliton microcomb based spectral domain optical coherence tomographyFeb 19 2019Spectral domain optical coherence tomography (SD-OCT) has become a widely applied minimally invasive technique for bio-medical imaging, and industrial process control. One of the most commonly used light source for SD-OCT is based on superluminescent ... More
Q-switched Dy:ZBLAN fiber lasers beyond 3 μm: comparison of pulse generation using acousto-optic modulation and inkjet-printed black phosphorusFeb 19 2019We report high-energy mid-infrared pulse generation by Q-switching of dysprosium-doped fiber lasers for the first time. Two different modulation techniques are demonstrated. Firstly, using active acousto-optic modulation, pulses are produced with up to ... More
Robust PT symmetry of two-dimensional fundamental and vortex solitons supported by spatially modulated nonlinearityFeb 19 2019The real spectrum of bound states produced by PT-symmetric Hamiltonians usually suffers breakup at a critical value of the strength of gain-loss terms, i.e., imaginary part of the complex potential. On the other hand, it is known that the PT-symmetry ... More
Systematic design of the color point of a white LEDFeb 19 2019Lighting is a crucial technology that is used every day. The introduction of the white light emitting diode (LED) that consists of a blue LED combined with a phosphor layer, greatly reduces the energy consumption for lighting. Despite the fast-growing ... More
All-optical reconfigurable chiral meta-moleculesFeb 18 2019Chirality is a ubiquitous phenomenon in the natural world. Many biomolecules without inversion symmetry such as amino acids and sugars are chiral molecules. Measuring and controlling molecular chirality at a high precision down to the atomic scale are ... More
Magnetic Field Control of Optical Transmission and Narrow Linewidth Superradiant Lasing by Strontium AtomsFeb 18 2019We study the magnetic field controlled optical transmission observed in [Phys. Rev. Lett. 118, 263601 (2017)] with ultra-cold ${}^{88} {\rm Sr}$ atoms trapped in a one-dimensional optical lattice inside an optical cavity. We show that this phenomenon ... More
Helical transport in coupled resonator waveguidesFeb 18 2019We show that a synthetic pseudospin-momentum coupling can be used to design quasi-one-dimensional disorder-resistant coupled resonator optical waveguides (CROW). In this structure, the propagating Bloch waves exhibit a pseudospin-momentum locking at specific ... More
Pulsing mechanism based on power adiabatic evolution of pump in Tm-doped fiber laserFeb 18 2019We prove an alternative pulsing mechanism based on power adiabatic evolution of pump in Tm-doped fiber laser. A pulsed laser technique, unlike Q-switching and gain-switching, is explored under the equilibrium between the stimulated emission and absorption. ... More
Classification of massive Dirac models with generic non-Hermitian perturbationsFeb 18 2019We present a systematic investigation of $d$-dimensional massive Dirac models perturbed by three different types of non-Hermitian terms: (i) non-Hermitian terms that anti-commute with the Dirac Hamiltonian, (ii) non-Hermitian kinetic terms, and (iii) ... More
Levitated cavity optomechanics in high vacuumFeb 18 2019We report dispersive coupling of an optically trapped silica nanoparticle ($143~$nm diameter) to the field of a driven Fabry-Perot cavity in high vacuum ($4.3\times 10^{-6}~$mbar). We demonstrate nanometer-level control in positioning the particle with ... More
Phase Synchronization in Stimulated Raman Process for Long Pulse Regime: Route for Wideband Coherent Spectrum GenerationFeb 18 2019We investigate the evolution of coherence property of noise-seeded Stokes wave in short (< 1 ps) and long pulse (> 1 ps) regimes. Nonlinear equations describing the evolution of pump and Stokes waves are solved numerically for both the regions. Our statistical ... More
Generating Lieb and super-honeycomb lattices by employing the fractional Talbot effectFeb 18 2019Hua Zhong and Yiqi Zhang and Milivoj R. Belic and Yanpeng Zhang We demonstrate a novel method for producing optically-induced Lieb and super-honeycomb lattices, by employing the fractional Talbot effect of specific periodic beam structures. Our numerical ... More
Integrated frequency comb laser with narrow intrinsic optical linewidth based on a dielectric waveguide feedback circuitFeb 18 2019We present an integrated hybrid semiconductor-dielectric (InP-Si$_3$N$_4$) waveguide laser that generates frequency combs at a wavelength around 1.5 $\mu$m with a record-low intrinsic optical linewidth of 34 kHz. This is achieved by extending the cavity ... More
Orientation-dependent transition rule in high-order harmonic generation from solidsFeb 18 2019We study the role of transition rule in high-order harmonic generation from solids driven by linearly polarized laser elds. The orientation-dependent transition dipoles can regulate the emergence of the multi-plateau structure. In the multi-plateau zone, ... More
A synthetic gauge field for two-dimensional time-multiplexed quantum random walksFeb 17 2019Temporal multiplexing provides an efficient and scalable approach to realize a quantum random walk with photons that can exhibit topological properties. But two dimensional time-multiplexed topological quantum walks studied so far have relied on generalizations ... More
An Antenna Array Initial Condition Calibration Method for Integrated Optical Phased ArrayFeb 17 2019This paper presents a modified rotating element electric field vector (modified REV) method to calibrate the antenna array initial condition of an optical phased array (OPA) device. The new method follows a similar sequential individual antenna phase ... More
Self-adaptive waveguide boundary for wideband multi-mode four-wave mixingFeb 16 2019We propose a new approach to provide wideband multi-mode four-wave mixing, independent of the intrinsic waveguide dispersion. We adopt concepts from quantum mechanics and sub-wavelength engineering to design an effective photon well, with a graded potential ... More
From self-organization in relativistic electron bunches to coherent synchrotron light: observation using a photonic time-stretch digitizerFeb 16 2019In recent and future synchrotron radiation facilities, relativistic electron bunches with increasingly high charge density are needed for producing brilliant light at various wavelengths, from X-rays to terahertz. In such conditions, interaction of electrons ... More
Arago spot formation in the time domainFeb 16 2019Using the space-time duality we theoretically and experimentally revisit the Arago spot formation in the time domain and explore the temporal emergence of a bright spot in the time shadow of an initial waveform. We describe the linear regime of propagation ... More
Faraday-Rotation in Iron Garnet Films Beyond Elemental SubstitutionsFeb 16 2019In previous decades significant efforts have been devoted to increasing the magneto-optical efficiency of iron garnet materials for the miniaturization of nonreciprocal devices such as isolators and circulators. Elemental substitutions or proper nano-structuring ... More
Optical vector analysis with attometer resolution, 90-dB dynamic range and THz bandwidthFeb 16 2019Optical vector analysis (OVA) having the capability to achieve magnitude and phase responses is essential for fabrication and application of emerging optical devices. However, the conventional OVA often have to make compromises among resolution, dynamic ... More
Cavity-enhanced high harmonic generation for XUV time-resolved ARPESFeb 15 2019With its direct correspondence to electronic structure, angle-resolved photoemission spectroscopy (ARPES) is a ubiquitous tool for the study of solids. When extended to the temporal domain, time-resolved (TR)-ARPES offers the potential to move beyond ... More
Plasmonic colours predicted by deep learningFeb 15 2019Picosecond laser pulses have been used as a surface colouring technique for noble metals, where the colours result from plasmonic resonances in the metallic nanoparticles created and redeposited on the surface by ablation and deposition processes. This ... More
Measuring algorithmic complexity in chaotic lasersFeb 15 2019Thanks to the simplicity and robustness of its calculation methods, algorithmic (or Kolmogorov) complexity appears as a useful tool to reveal chaotic dynamics when experimental time series are too short and noisy to apply Takens' reconstruction theorem. ... More
Nonlinear response from optical bound states in the continuumFeb 15 2019We consider nonlinear effects in scattering of light by a periodic structure supporting optical bound states in the continuum. In the spectral vicinity of the bound states the scattered electromagnetic field is resonantly enhanced triggering optical bistability. ... More
Single-step fabrication of surface waveguides in fused silica with few-cycle laser pulsesFeb 15 2019Direct laser writing of surface waveguides with ultrashort pulses is a crucial achievement towards all-laser manufacturing of photonic integrated circuits sensitive to their environment. In this Letter, few-cycle laser pulses (with a sub-10 fs duration) ... More
Flat band localization due to self-trapped orbitalFeb 15 2019We discover a new wave localization mechanism in a periodic system without any disorder, which can produce a novel type of perfect flat band and is distinct from the known localization mechanisms, i.e., Anderson localization and flat band lattices. The ... More
Near-perfect absorber as a subwavelength thickness spatial frequency filter for optical image processingFeb 15 2019Spatial frequency filtering is a fundamental enabler of information processing methods in biological and technical imaging. Most filtering methods, however, require either bulky and expensive optical equipment or some degree of computational processing. ... More
Molecular rotation movie filmed with high-harmonic generationFeb 15 2019Direct imaging of molecular dynamics is a long-standing goal in physics and chemistry. As an emerging tool, high-harmonic spectroscopy (HHS) enables accessing molecular dynamics on femtosecond to attosecond time scales. However, decoding information from ... More
Sub-micron spatial resolution in far-field Raman imaging via positivity constrained super-resolutionFeb 14 2019Raman microscopy is a valuable tool for detecting physical and chemical properties of a sample material. When probing nanomaterials or nanocomposites the spatial resolution of Raman microscopy is not always adequate as it is limited by the optical diffraction ... More
Coexistence and interactions between nonlinear states with different polarizations in a monochromatically driven passive Kerr resonatorFeb 14 2019We report on experimental observations of coexistence and interactions between nonlinear states with different polarizations in a passive Kerr resonator driven at a single carrier frequency. Using a fiber ring resonator with adjustable birefringence, ... More
Orbital angular momentum coupling in elastic photon-photon scatteringFeb 14 2019In this letter, we investigate the effect of orbital angular momentum (OAM) on elastic photon-photon scattering in vacuum for the first time. We define exact solutions to the vacuum electro-magnetic wave equation which carry OAM. Using those, the expected ... More
Indium tin oxide nanoparticle:TiO$_{2}$:air layers for one-dimensional multilayer photonic structuresFeb 14 2019In this work we study the optical properties, by means of the transfer matrix method, of one-dimensional photonic crystals in which layers of silica nanoparticles are alternated with layers of indium tin oxide nanoparticle (ITO) / titania nanoparticle ... More
Temporal contrast reduction techniques for high dynamic-range single-shot temporal contrast measurementFeb 14 2019A single-shot characterization of the temporal contrast of a petawatt laser pulse with a high dynamic-range, is important not only for improving conditions of the petawatt laser facility itself, but also for various high-intensity laser physics experiments, ... More
An Ultra-Wideband THz Absorber Based on Graphene Disks for TM and TE ModesFeb 14 2019In this research paper, an unsophisticated configuration of the ultra-wideband THz absorber for transverse electric (TE) and transverse magnetic (TM) modes of the incident THz wave is proposed. The mentioned absorber consists of two layers of graphene ... More
Supercontinuum generation without residual pump peak through multiple coherent pump seedsFeb 14 2019Residual pump peak in fiber-based supercontinuum, as a general phenomenon, limits its practical application. We report a novel supercontinuum generation (SCG) in a conventional highly nonlinear fiber (HNLF) through multiple coherent pump technique, which ... More
Nonlinear Depolarization of Light in Optical Communication FiberFeb 14 2019We report the experimental observation of a novel transmission phenomenon in optical long-haul communication systems. Un-polarized ASE depolarizes via nonlinear fiber interactions a cw laser light during their co-propagation which leads to small but measurable ... More
A fiber-integrated single photon source emitting at telecom wavelengthsFeb 13 2019Fiber-coupled single photon sources are essential components of photonics-based quantum information processors. Most fiber-coupled single photon sources require careful alignment between fibers and quantum emitters. In this work, we present an alignment-free ... More
Dynamical trapping of light in harmonically breathing waveguide latticesFeb 13 2019A new strategy for trapping quantum particles is presented, which allow us to simulate an effective harmonic oscillator potential trap wherever is desired. The approach is based on harmonic contraction and expansion of the system around a fixed point ... More
Coherent Control of Two-Dimensional ExcitonsFeb 13 2019Electric dipole radiation can be controlled by coherent optical feedback, as has previously been studied by modulating the photonic environment for point dipoles placed both in optical cavities and near metal mirrors. In experiments involving fluorescent ... More
Laser wakefield driven generation of isolated CEP-tunable intense sub-cycle pulsesFeb 13 2019Sources of intense, ultra-short electromagnetic pulses are enabling applications such as attosecond pulse generation, control of electron motion in solids and the observation of reaction dynamics at the electronic level. For such applications both high-intensity ... More
Nonlinear optical properties of polycrystalline silicon core fibers from Telecom wavelengths into the mid-infrared spectral regionFeb 13 2019Polycrystalline silicon core fibers (SCFs) fabricated via the molten core drawing (MCD) method are emerging as a flexible optoelectronic platform. Here, the optical transmission properties of MCD SCFs that have been tapered down to a few micrometer-sized ... More
Evaluating tear clearance rate with optical coherence tomographyFeb 13 2019Purpose: To assess the early-phase of tear clearance rate (TCR) with anterior segment optical coherence tomography (OCT) and to determine the association between TCR and other clinical measures of the tear film in a group of young subjects with different ... More
Regularization of Vertical-Cavity Surface-Emitting Lasers emission by periodic non-Hermitian potentialsFeb 13 2019We propose a novel physical mechanism based on periodic non-Hermitian potentials to efficiently control the complex spatial dynamics of broad-area lasers, particularly in Vertical-Cavity Surface-Emitting Lasers (VCSELs), achieving a stable emission of ... More
Coherent supercontinuum generation in tellurite glass regular lattice photonic crystal fibersFeb 13 2019We report on designing, fabrication and experimental characterization of highly nonlinear, tellurite glass photonic crystal fibers with engineered normal dispersion characteristics for coherent supercontinuum generation. Effectively single mode, air-hole ... More
Tutorial on Optical Forces in Optical TweezersFeb 13 2019Recently, the Nobel prize in physics was awarded for the invention of optical tweezers. Thus far, they have been used as tools to obtain measurements of microscopic systems, mainly by harnessing the optical forces. For quite some time, it has been used ... More
Unidirectional light transmission by two-layer nanostructures interacting via optical near-fieldsFeb 13 2019We experimentally demonstrate unidirectional light transmission through two-layer nanostructured materials considering that the horizontal-to-vertical-polarization conversion efficiency in the forward direction and the vertical-to-horizontal efficiency ... More
Correlated emission of X-ray and sound from water film irradiated by femtosecond laser pulsesFeb 13 2019Simultaneous measurements of hard X-ray by a Geiger counter and audible sound (10 Hz-20kHz) by a microphone from a thin water film in air were carried out under intense single and double pulse irradiations of femtosecond laser (35 fs, 800 nm, 1 kHz). ... More
The effect of plasma-core induced self-guiding on phase matching of high-order harmonic generation in gasesFeb 12 2019In this work we numerically study a self-guiding process in which ionization plays a dominant role and analyze its effect on high-order harmonic generation (HHG) in gases. Although this type of self-guiding --- termed as plasma-core induced self-guiding ... More
Quantitative orbital angular momentum measurement of perfect vortex beamsFeb 12 2019Perfect (optical) vortices (PVs) have the mooted ability to encode orbital angular momentum (OAM) onto the field within a well-defined annular ring. Although this makes the near-field radial profile independent of OAM, the far-field radial profile nevertheless ... More
Polaritonic frequency-comb generation and breather propagation in a negative-index metamaterial with a cold four-level atomic mediumFeb 12 2019We develop a concept for a waveguide that exploits spatial control of nonlinear surface-polaritonic waves. Our scheme includes an optical cavity with four-level $\text{N}$-type atoms in a lossless dielectric placed above a negative-index metamaterial ... More
Complex-k modes of plasmonic chain waveguidesFeb 12 2019Nanoparticle chain waveguide based on negative-epsilon material is investigated through a finite-element-based mode solver which derives complex propagation constants ($k$) of propagating modes. We first look into waveguiding behavior of chain waveguides ... More
Wavefront shaping for optimized many-mode Kerr beam self-cleaning in graded-index multimode fiberFeb 12 2019We report experimental results, showing that the Kerr beam self-cleaning of many low-order modes in a graded-index multimode fiber can be controlled thanks to optimized wavefront shaping of the coherent excitation beam. Adaptive profiling of the transverse ... More
Four-wave mixing and enhanced analogue Hawking effect in a nonlinear optical waveguideFeb 12 2019We study the scattering of light on a soliton propagating in a waveguide. When not applying the rotating wave approximation, we show that the linearized wave equation governing perturbations has the same structure as that governing phonon propagation ... More
Echo-Based Quantum MemoryFeb 12 2019In this book chapter we review photon echo based schemes for optical quantum memory. We outline the basic principles of the Atomic Frequency Comb (AFC), Gradient Echo Memory (GEM) and Rephased Amplified Spontaneous Emission (RASE) protocols. We describe ... More
Binary square axicon with chiral focusing properties for optical trappingFeb 12 2019We introduce a novel phase-only diffractive optical element called chiral binary square axicon (CBSA). The CBSA is designed by linearly rotating the square half-period zones of the binary square axicon with respect to one another. A quadratic phase mask ... More
Comparison of three approaches to light scattering by dilute cold atomic ensemblesFeb 12 2019Collective effects in atom-light interaction is of great importance for cold-atom-based quantum devices or fundamental studies on light transport in complex media. Here we discuss and compare three different approaches to light scattering by dilute cold ... More
Twin-beam-enhanced displacement measurement of a membrane in a cavityFeb 12 2019Ultrasensitive measurement of a small displacement is an essential goal in various applications of science and technology, ranging from large-scale laser interferometric gravitational wave detectors to micro-electro-mechanical-systems-based force microscopy. ... More
Unidirectional reflectivity in lossy thin filmsFeb 11 2019Inspired by non-Hermitian systems, we study reflection and transmission in a stack of thin films composed by the repetition of a bipartite unit cell. We aim for controlled reflection and transmission using lossless and lossy materials in order to develop ... More
High-harmonic generation in Su-Schrieffer-Heeger chainsFeb 11 2019Su-Schrieffer-Heeger (SSH) chains are the simplest model systems that display topological edge states. We calculate high-harmonic spectra of SSH chains that are coupled to an external laser field of a frequency much smaller than the band gap. We find ... More
Photonic analogues of the Haldane and Kane-Mele modelsFeb 11 2019The condensed matter Haldane and Kane-Mele models revolutionized the understanding of what is an "insulator", as they unveiled novel classes of media that behave as metals near the surface, but are insulating in the bulk. Here, we propose exact electromagnetic ... More
Suppression of Spectral Diffusion by Anti-Stokes Excitation of Quantum Emitters in Hexagonal Boron NitrideFeb 11 2019Solid-state quantum emitters are garnering a lot of attention due to their role in scalable quantum photonics. A notable majority of these emitters, however, exhibit spectral diffusion due to local, fluctuating electromagnetic fields. In this work, we ... More
Klein-Gordon representation of acoustic waves and topological origin of surface acoustic modesFeb 10 2019Recently, it was shown that surface electromagnetic waves at interfaces between continuous homogeneous media (e.g., surface plasmon-polaritons at metal-dielectric interfaces) have a topological origin [K.Y. Bliokh et al., Nat. Commun. 10, 580 (2019)]. ... More
High-harmonic generation from an epsilon-near-zero materialFeb 10 2019High-harmonic generation (HHG) from a compact, solid-state medium is highly desirable for applications such as coherent attosecond pulse generation and extreme ultra-violet (EUV) spectroscopy, yet the typically weak conversion of pump light to HHG can ... More
Tests of cryogenic Fabry-Perot cavity with mirrors on different substratesFeb 09 2019Experiments were performed with Fabry-Perot optical resonators in vacuum at low temperatures. Mirrors were applied on substrates of various optical materials. The infrared laser with a wavelength of 1.064 microns was used. The pump power at the maximum ... More
Polarization sensitive laser intensity inside femtosecond filament in airFeb 09 2019Polarization dependence on clamping intensity inside femtosecond filament was experimentally measured in air. By tuning the laser pulse ellipse from linear polarization to circular polarization, the measured clamping intensity inside laser filament is ... More
Supersymmetric microring laser arraysFeb 08 2019Coherent combination of emission power from an array of coupled semiconductor lasers operating on the same chip is of fundamental and technological importance. In general, the nonlinear competition among the array supermodes can entail incoherence and ... More
Using Automatic Differentiation as a General Framework for Ptychographic ReconstructionFeb 08 2019Coherent diffraction imaging methods enable imaging beyond lens-imposed resolution limits. In these methods, the object can be recovered by minimizing an error metric that quantifies the difference between diffraction patterns as observed, and those calculated ... More
Using Automatic Differentiation as a General Framework for Ptychographic ReconstructionFeb 08 2019Feb 12 2019Coherent diffraction imaging methods enable imaging beyond lens-imposed resolution limits. In these methods, the object can be recovered by minimizing an error metric that quantifies the difference between diffraction patterns as observed, and those calculated ... More
Topology optimization of freeform large-area metasurfacesFeb 08 2019We demonstrate optimization of optical metasurfaces over $10^5$--$10^6$ degrees of freedom in two and three dimensions, 100--1000+ wavelengths ($\lambda$) in diameter, with 100+ parameters per $\lambda^2$. In particular, we show how topology optimization, ... More
Low-temperature infrared dielectric function of hyperbolic $α$-quartzFeb 08 2019We report the infrared dielectric properties of $\alpha$-quartz in the temperature range from $1.5\ \mathrm{K}$ to $200\ \mathrm{K}$. Using an infrared free-electron laser, far-infrared reflectivity spectra of a single crystal $y$-cut were acquired along ... More
Space-compatible cavity-enhanced single-photon generation with hexagonal boron nitrideFeb 08 2019Sources of pure and indistinguishable single-photons are critical for near-future optical quantum technologies. Recently, color centers hosted by two-dimensional hexagonal boron nitride (hBN) have emerged as a promising platform for high luminosity room ... More
Anomalous quantum Hall effect of light in Bloch-wave modulated photonic crystalsFeb 07 2019Effective magnetic fields have enabled unprecedented manipulation of neutral particles including photons. In most studied cases, the effective gauge fields are defined through the phase of mode coupling between spatially discrete elements, such as optical ... More
Opto-mechanical resonator-enhanced atom interferometryFeb 07 2019We combine an optical-mechanical resonator with an atom interferometer. A classical cantilever and matter waves sense their acceleration with respect to a joint reference. Apart from research on macroscopic opto-mechanical quantum objects, applications ... More
The statistics of chaos in a bursting laserFeb 07 2019We demonstrate experimentally how semiconductor lasers subjected to double optical feedback change the statistics of their chaotic spiking dynamics from Gaussian to long-tail Power Law distributions associated to the emergency of bursting. These chaotic ... More
A 30 GHz electro-optic frequency comb spanning 300 THz in the near infrared and visibleFeb 07 2019Beginning with a continuous wave laser at 1064 nm, we generate a 30 GHz electro-optic frequency comb which contains 100 lines spanning 3 THz. The initial comb is subsequently amplified, spectrally broadened in normal dispersion photonic crystal fiber, ... More
Direct imaging of the energy transfer enhancement between two dipoles in a photonic cavityFeb 07 2019Photonic cavities are gathering a large interest to enhance the energy transfer between two dipoles, with far-reaching consequences for applications in photovoltaics, lighting sources and molecular biosensing. However, experimental difficulties in controlling ... More
Spectral noise in quantum frequency down-conversion from the visible to the telecommunication C-bandFeb 07 2019We report a detailed study of the noise properties of a visible-to-telecom photon frequency converter based on difference frequency generation (DFG). The device converts 580 nm photons to 1541 nm using a strong pump laser at 930 nm, in a periodically ... More
Blind focusing through strongly scattering media using wavefront shaping with nonlinear feedbackFeb 07 2019Scattering prevents light from being focused in turbid media. The effect of scattering can be negated through wavefront shaping techniques when a localized form of feedback is available. Even in the absence of such a localized reporter, wavefront shaping ... More
Freestanding metasurfaces for optical frequenciesFeb 07 2019We present freestanding metasurfaces operating at optical frequencies with a total thickness of only 40$\,$nm. The metasurfaces are fabricated by focused ion beam milling of nanovoids in a carbon film followed by thermal evaporation of gold and plasma ... More
Single-pass, second harmonic generation of ultrafast, higher order vector vortex beams at blueFeb 07 2019We report a novel experimental scheme for single-pass second harmonic generation (SHG) of vector vortex beam in the blue. Using an ultrafast Ti:Sapphire laser of pulse width ~17 fs and a set of spiral phase plates in polarization based Mach-Zehnder interferometer ... More
Coherent vortex dynamics in a strongly-interacting superfluid on a silicon chipFeb 07 2019Two-dimensional superfluidity and quantum turbulence are directly connected to the microscopic dynamics of quantized vortices. However, surface effects have prevented direct observations of coherent vortex dynamics in strongly-interacting two-dimensional ... More
Optimal design strategy for non-Abelian geometric phases using Abelian gauge fields based on quantum metricFeb 07 2019Geometric phases, which are ubiquitous in quantum mechanics, are commonly more than only scalar quantities. Indeed, often they are matrix-valued objects that are connected with non-Abelian geometries. Here we show how generalized, non-Abelian geometric ... More
Dual-Reference Design for Holographic Coherent Diffraction ImagingFeb 07 2019A new reference design is introduced for Holographic Coherent Diffraction Imaging. This consists of two reference portions - being "block" and "pinhole" shaped regions - adjacent to the imaging specimen. Expected error analysis on data following a Poisson ... More
Raman Laser Switching Induced by Cascaded Light ScatteringFeb 07 2019We show that, in multimode Raman lasers, cascaded light scattering (CLS) not only extends the optical frequency range, but could also modulate the laser dynamics. The origin of this phenomenon is based on the fact that many Raman lasing modes are directly ... More
Enhanced widefield quantum sensing with nitrogen-vacancy ensembles using diamond nanopillar arraysFeb 07 2019Quantum sensors based on optically active defects in diamond such as the nitrogen vacancy (NV) centre represent a promising platform for nanoscale sensing and imaging of magnetic, electric, temperature and strain fields. Enhancing the optical interface ... More
A Hybrid Strategy for the Discovery and Design of Photonic NanostructuresFeb 06 2019Feb 07 2019Designing complex physical systems, including photonic structures, is typically a tedious trial-and-error process that requires extensive simulations with iterative sweeps in multi-dimensional parameter space. To circumvent this conventional approach ... More
One-Way Hyperbolic Metasurfaces Based on Synthetic MotionFeb 06 2019Moving metasurfaces support guided waves exhibiting unusual optical properties, including strong anisotropy, nonreciprocity, and hyperbolic dispersion. However, for these phenomena to be noticeable, high speeds are typically required, challenging their ... More
Ultrafast dynamics and surface plasmon properties of Silicon upon irradiation with mid-infrared femtosecond laser pulsesFeb 06 2019We present a theoretical investigation of the yet unexplored ultrafast processes and dynamics of the produced excited carriers upon irradiation of Silicon with femtosecond pulsed lasers in the mid-infrared (mid-IR) spectral region. The evolution of the ... More
Parametric Resonances and Resonant Delocalization in Quasi-Phase Matched Photon-pair Generation and Quantum Frequency ConversionFeb 06 2019The existing widely-accepted theory of photon-pair generation via spontaneous down-conversion (SPDC) in nonlinear optical crystals and waveguides is incomplete, as it fails to account for the important physical phenomenon of parametric resonances. We ... More
Heating in Nanophotonic Traps for Cold AtomsFeb 06 2019Laser-cooled atoms that are trapped and optically interfaced with light in nanophotonic waveguides provide a powerful platform for quantum optics research. A long-standing challenge for such systems is heating of the atomic motion with rates exceeding ... More