A5002464590- Quantum Information and Cryptography
- Atomic and Subatomic Physics Research
- Mechanical and Optical Resonators
- Quantum Computing Algorithms and Architecture
- Advanced Condensed Matter Physics
- Quantum and electron transport phenomena
- Quantum optics and atomic interactions
- Magnetic and transport properties of perovskites and related materials
- Quantum Mechanics and Applications
- Topological Materials and Phenomena
- Gold and Silver Nanoparticles Synthesis and Applications
- Plasmonic and Surface Plasmon Research
- Magneto-Optical Properties and Applications
- Photonic and Optical Devices
- Random lasers and scattering media
- Neural Networks and Reservoir Computing
- Quantum, superfluid, helium dynamics
- Optical Network Technologies
- ZnO doping and properties
- Silicon Nanostructures and Photoluminescence
- Advanced Optical Sensing Technologies
- Spectroscopy Techniques in Biomedical and Chemical Research
- Advanced Electron Microscopy Techniques and Applications
- Magnetic properties of thin films
- Nanowire Synthesis and Applications
Oak Ridge National Laboratory
2019-2023
Quantum Science Center
2019-2023
Vanderbilt University
2013-2020
Practical quantum networking architectures are crucial for scaling the connection of resources. Yet network testbeds have thus far underutilized full capabilities modern lightwave communications, such as flexible-grid bandwidth allocation. In this work, we implement flex-grid entanglement distribution in a deployed first time, connecting nodes three distinct campus buildings time-synchronized via Global Positioning System (GPS). We quantify quality distributed polarization log-negativity,...
We summarize the recent progress of Axion Longitudinal Plasma Haloscope (ALPHA) Consortium, a new experimental collaboration to build plasma haloscope search for axions and dark photons. The is novel method detection resonant conversion light matter ALPHA will be sensitive QCD over almost decade parameter space, potentially discovering resolving strong $CP$ problem. Unlike traditional cavity haloscopes, which are generally limited in volume by Compton wavelength matter, haloscopes use wire...
The combination of non-trivial band topology and symmetry breaking phases gives rise to novel quantum states phenomena such as topological superconductivity, anomalous Hall effect axion electrodynamics. Evidence intertwined charge density wave (CDW) superconducting order parameters has recently been observed in a kagome material AV3Sb5 (A=K,Rb,Cs) that features Z2 invariant the electronic structure. However, origin CDW its intricate interplay with state yet be determined. Here, using hard...
Localized surface plasmon (LSP) enhanced waveguide-type ultraviolet light-emitting diodes (LEDs) were fabricated by sputtering Ag nanoparticles (Ag-NPs) onto ZnO/MgZnO core/shell nanorod array (CS-NRA)/p-GaN heterostructures. A ∼9-fold enhancement of ZnO electroluminescence (EL) was demonstrated the Ag-NPs decorated LED compared with device without Ag-NPs. Angle-dependent EL measurements, as well finite-difference time-domain simulations intensity spatial distribution, confirmed transmission...
As practical quantum networks prepare to serve an ever-expanding number of nodes, there has grown a need for advanced auxiliary classical systems that support the protocols and maintain compatibility with existing fiber-optic infrastructure. We propose demonstrate local area network design addresses current deployment limitations in timing security scalable fashion using commercial off-the-shelf components. First, we employ White Rabbit switches synchronize three remote nodes ultra-low...
Quantum process learning is a fundamental primitive that draws inspiration from machine with the goal of better studying dynamics quantum systems. One approach to compilation, whereby an analog operation digitized by compiling it into series basic gates. While there has been significant focus on for discrete-variable systems, continuous-variable (CV) framework received comparatively less attention. We present experimental implementation CV compiler uses two mode-squeezed light learn Gaussian...
Abstract The evolution of wide bandgap semiconductor materials has led to dramatic improvements for electronic applications at high powers and temperatures. However, the propensity extended defects provides significant challenges implementing these in commercial optical applications. While a range spectroscopic microscopic tools have been developed identifying characterizing defects, such techniques typically offer either technique exclusively, and/or may be destructive. Scattering‐type...
CsYbSe$_2$, a recently identified quantum spin liquid (QSL) candidate, exhibits strong crystal electric field (CEF) excitations. Here, we identify phonon and CEF modes with Raman spectroscopy observe CEF-phonon mixing resulting in vibronic bound state. Complex, mesoscale interplay between is observed real space, an unexpected nearly resonant condition satisfied, yielding up to fifth-order combination modes, total of 17 the spectra. This study paves way coherent control possible QSL ground...
The absence of clear signals from particle dark matter in direct detection experiments motivates new approaches disparate regions viable parameter space. In this Snowmass white paper, we outline the Windchime project, a program to build large array quantum-enhanced mechanical sensors. ultimate aim is detector capable searching for Planck mass-scale purely through its gravitational coupling ordinary matter. shorter term, search number other physics targets, especially some ultralight...
Surface‐enhanced Raman spectroscopy (SERS) has potential for unique clinical, environmental, and military applications, among many others, but it is limited by a rapid decrease in signal with distance from the sensing surface. For this reason, much study of SERS‐based biosensing involves chemical or physical adsorption analytes to an active Adsorption, however, limits types that can be detected detection sensitivity. The three‐dimensional closely packed architecture zinc oxide (ZnO)...
Abstract Magneto‐optical microscopies, including optical measurements of magnetic circular dichroism, are increasingly ubiquitous tools for probing spin‐orbit coupling, charge‐carrier g‐factors, and chiral excitations in matter, but the minimum detectable signal classical dichroism is fundamentally limited by shot‐noise limit readout field. Here, a two‐mode squeezed light source used to improve 3 decibels compared with state‐of‐the‐art measurements, even relatively lossy samples like terbium...
Solid-state single-photon emitters (SPEs) such as the bright, stable, room-temperature defects within hexagonal boron nitride (hBN) are of increasing interest for quantum information science applications. To date, atomic and electronic origins SPEs hBN not well understood, no studies have reported photochromism or explored cross-correlations between SPEs. Here, we combine irradiation-time dependent measures efficiency microphotoluminescence (${\mu}$PL) spectroscopy with two-color Hanbury...
Superconducting nanowire single photon detectors (SNSPDs) are typically used as single-mode-fiber-coupled single-pixel detectors, but large area increasingly critical for applications ranging from microscopy to free-space quantum communications. Here, we explore changes in the rising edge of readout pulse large-area SNSPDs a function bias current, optical spot size on detector, and number photons per pulse. We observe bimodal distribution rise times show that probability slow time increases...
The nanoscale optical response of surface plasmons in three-dimensional metallic nanostructures plays an important role many nanotechnology applications, where precise spatial and spectral characteristics plasmonic elements control device performance. Electron energy loss spectroscopy (EELS) cathodoluminescence (CL) within a scanning transmission electron microscope have proven to be valuable tools for studying plasmonics at the nanoscale. Each technique has been used separately, producing...
Abstract Zinc oxide (ZnO) nanowires are widely studied for use in ultraviolet optoelectronic devices, such as nanolasers and sensors. Nanowires (NWs) with an MgO shell exhibit enhanced band‐edge photoluminescence (PL), a result previously attributed to passivation of ZnO defects. However, we find that processing the NWs under low oxygen partial pressure leads MgO‐thickness‐dependent PL enhancement owing formation optical cavity modes. Conversely, higher support neither mode nor enhancement....
The notion that phonons can carry pseudo-angular momentum has many major consequences, including topologically protected phonon chirality, Berry curvature of band structure, and the Hall effect. When a is resonantly coupled to an orbital state split by its crystal field environment, so-called vibronic bound forms. Here, observed in NaYbSe
In recent years, distributed quantum sensing has gained interest for a range of applications requiring networks sensors, from global-scale clock synchronization to high energy physics. particular, network entangled sensors can improve not only the sensitivity beyond shot noise limit, but also enable Heisenberg scaling with number sensors. Here, using bright twin beams, we theoretically and experimentally demonstrate detection linear combination two phases limit truncated SU(1,1)...
Superconducting nanowire single-photon detectors (SNSPDs) offer high-quantum-efficiency and low-dark-count-rate detection. In a growing number of cases, large magnetic fields are being incorporated into quantum microscopes, nanophotonic devices, sensors for nuclear high-energy physics that rely on SNSPDs, but superconducting devices generally perform poorly in fields. Here, we demonstrate robust performance amorphous SNSPDs up to $\ifmmode\pm\else\textpm\fi{}6$ T with negligible dark-count...
We describe the operation of a free-space confocal optical microscope operated in dilution refrigerator. The is installed on cold insertable probe to enable fast sample exchange while refrigerator held at low temperatures. A vector magnet provides 6 T field normal and 1 fields arbitrary angles. variety microscopies spectroscopies, including photoluminescence, Raman, magneto-optical Kerr effect, spin relaxometry measurements are described, some challenges associated with performing these...
Abstract Magneto‐optical sensors including spin noise spectroscopies and magneto‐optical Kerr effect microscopies are now ubiquitous tools for materials characterization that can provide new understanding of dynamics, hyperfine interactions, spin‐orbit charge‐carrier g‐factors. Both interferometric intensity‐difference measurements photon‐shot‐noise‐limited sensitivity, but further improvements in sensitivity with classical resources require either increased laser power induce unwanted...
We implement a continuous-variable quantum compiler that can learn linear phase operation with fourfold increase in precision and factor of 80 reduction time to solution when resources are used.
We explore electron-phonon dynamics in hBN defects and observe $\text{g}^{(2)}(0)=0.20$ a phonon replica $\text{g}^{(2)}(0)=0.18$ between the zero-phonon line, we examine Purcell enhancement of replicas with phononic cavities.
Motivated by the possibility of enhanced magnetic fluctuations in exfoliated α-RuCl3 flakes, we study magneto-Raman spectra multilayer out-of-plane fields −6 to 6 T at temperatures 670 mK 4 K. While literature currently suggests that bulk is an antiferromagnetic zigzag phase with R3̅ symmetry low temperatures, do not observe temperatures. saw no field-driven transitions, Raman modes exhibit unexpected stochastic shifts response applied field are above uncertainties inferred from Bayesian...
We show how extended defects in wide bandgap semiconductors manifest the nanoscale infrared phonon response probed by scattering-type scanning near-field optical microscopy (s-SNOM). correlate s-SNOM of various 4H-SiC with UV-photoluminescence, secondary electron and channeling contrast imaging, transmission microscopy. identify evidence step-bunching, recombination-induced stacking faults, threading screw dislocations, also demonstrate interaction surface polaritons defects. Our results...