A5019834268- Laser-Plasma Interactions and Diagnostics
- Laser-Matter Interactions and Applications
- Laser-induced spectroscopy and plasma
- Laser Design and Applications
- Particle Accelerators and Free-Electron Lasers
- Aerodynamics and Acoustics in Jet Flows
- High-pressure geophysics and materials
- Acoustic Wave Phenomena Research
- Terahertz technology and applications
- Silicon Carbide Semiconductor Technologies
- Advanced X-ray Imaging Techniques
- Gyrotron and Vacuum Electronics Research
- Space Satellite Systems and Control
- Wind and Air Flow Studies
- Image and Signal Denoising Methods
- Ocular and Laser Science Research
- Thin-Film Transistor Technologies
- Advanced Fiber Laser Technologies
- Plasma Diagnostics and Applications
- Laser Material Processing Techniques
- Silicon and Solar Cell Technologies
- Magnetic confinement fusion research
- Photonic and Optical Devices
- Atomic and Molecular Physics
- Meteorological Phenomena and Simulations
University of Rochester
2022-2025
Energetics (United States)
2023-2025
University of California, Los Angeles
2020-2023
Applied Energetics (United States)
2022-2023
SLAC National Accelerator Laboratory
2021
Alfred I. duPont Hospital for Children
2020
Brigham Young University
2015-2018
The University of Texas Southwestern Medical Center
2018
Miller College
2016
Northwestern University
2016
A laser pulse composed of a fundamental and properly phased second harmonic exhibits an asymmetric electric field that can drive time-dependent current photoionized electrons. The produces ultrashort burst terahertz (THz) radiation. When driven by conventional pulse, the THz radiation is emitted into cone with angle determined dispersion medium. Here we demonstrate programmable-velocity intensity peak spatiotemporally structured, two-color be used to control emission angle, focal spot,...
Fully relativistic particle-in-cell (PIC) simulations are crucial for advancing our knowledge of plasma physics. Modern supercomputers based on graphics processing units (GPUs) offer the potential to perform PIC unprecedented scale, but require robust and feature-rich codes that can fully leverage their computational resources. In this work, demand is addressed by adding GPU acceleration code Osiris . An overview algorithm, which features a CUDA extension underlying Fortran architecture,...
"Flying focus" techniques produce laser pulses with dynamic focal points that travel distances much greater than a Rayleigh length. The implementation of these in laser-based applications requires the design optical configurations can both extend range and structure radial group delay. This article describes method for designing ultrashort flying focus programmable-trajectory points. is illustrated by several examples employ an axiparabola extending either reflective echelon or deformable...
ABSTRACT Loss of the skin barrier facilitates colonization underlying tissues with various bacteria, where they form biofilms that protect them from antibiotics and host responses. Such wounds then become chronically infected. Topical antimicrobials are a major component chronic wound therapy, yet currently available topical vary in their effectiveness on biofilm-forming pathogens. In this study, we evaluated efficacy Next Science gel technology (NxtSc), novel agent designed to kill...
Laser-plasma accelerators (LPAs) driven by picosecond-scale, kilojoule-class lasers can generate particle beams and x-ray sources that could be utilized in experiments multi-kilojoule, high-energy-density science (HEDS) drivers such as the OMEGA laser at Laboratory for Laser Energetics (LLE) or National Ignition Facility Lawrence Livermore Laboratory. This paper reports on development of first LPA a short-pulse, (OMEGA EP) connected to multi-kilojoule HEDS driver (OMEGA). In experiments,...
The longitudinal coherence of X-ray free-electron lasers (XFELs) in the self-amplified spontaneous emission regime could be substantially improved if high brightness electron beam pre-bunched on radiated wavelength-scale. Here, we show that it is indeed possible to realize such current modulated at angstrom scale by exciting a nonlinear wake across periodically plasma-density downramp/plasma cathode. density modulation turns and off injection electrons while downramp provides unique mapping...
Electrostatic waves play a critical role in nearly every branch of plasma physics from fusion to advanced accelerators, astro, solar, and ionospheric physics. The properties planar electrostatic are fully determined by the conditions, such as density, temperature, ionization state, or details distribution functions. Here we demonstrate that wave packets structured with space-time correlations can have independent conditions. For instance, an appropriately packet travel at any group velocity,...
The accelerated electron spectrum from high-intensity laser–solid interaction is often conveniently described using a Boltzmann distribution, whose temperature known within the field as hot-electron temperature. importance of highlighted by sheer number experimental and simulation studies on subject over past three decades. Recently, multi-kJ, multi-ps pulses have yielded spectra with temperatures far beyond expected ponderomotive result. Expressions that predict considering laser parameters...
Disseminated herpes simplex virus (HSV) infection in neonates represents a devastating entity that yields high mortality. Acyclovir is the primary antiviral agent used to treat life-threatening HSV infections neonates; however, even though has reduced morbidity overall from these infections, mortality with disseminated disease remains high. Currently, our knowledge, no data exist regarding therapeutic drug monitoring of acyclovir setting extracorporeal life support (ECLS) or continuous renal...
In this paper, quantitative understanding of a frequency-domain nonlinearity indicator is developed. The derived from an ensemble-averaged, version the generalized Burgers equation, which can be rearranged in order to directly compare effects nonlinearity, absorption, and geometric spreading on pressure spectrum level with frequency distance. nonlinear effect calculated using pressure-squared-pressure quadspectrum. Further theoretical development has given expression for role normalized...
We report ${T}_{2}$ spin coherence times for electronic states localized in Si vacancies $4H\text{\ensuremath{-}}\mathrm{SiC}$. Our study included two SiC samples that were irradiated with 2 MeV protons at different fluences (${10}^{13}$ and ${10}^{14}\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{\ensuremath{-}2}$) order to create unique defect concentrations. Using optically detected magnetic resonance echo, the each sample measured across a range of temperatures from 8 295 K. All...
Spatiotemporal control encompasses a variety of techniques for producing laser pulses with dynamic intensity peaks that move independently the group velocity. This controlled motion peak offers new approach to optimizing laser-based applications and enhancing signatures fundamental phenomena. Here, we demonstrate spatiotemporal plasma optic. A chirped pulse focused by lens exhibits moving focal point, or “flying focus,” can travel at an arbitrary, predetermined Unlike currently used...
Simulations of intense laser-solid interactions reveal the optimal configuration laser intensity and duration at constant energy to maximize 1--5 MeV x-ray yield. A phenomenological model predicts hot-electron temperature as a function parameters density scale length.
In a laser wakefield accelerator (LWFA), an intense pulse excites plasma wave that traps and accelerates electrons to relativistic energies. When the overlaps accelerated electrons, it can enhance energy gain through direct acceleration (DLA) by resonantly driving betatron oscillations of in wave. The particle-in-cell (PIC) algorithm, although often tool choice study DLA, contains inherent errors due numerical dispersion time staggering electric magnetic fields. Further, conventional PIC...
The quality of electron beams produced from plasma-based accelerators, i.e., normalized brightness and energy spread, has made transformative progress in the past several decades both simulation experiment. Recently, full-scale particle-in-cell (PIC) simulations have shown that with unprecedented (${10}^{20}--{10}^{21}\text{ }\text{ }\mathrm{A}/{\mathrm{m}}^{2}/{\mathrm{rad}}^{2}$) 0.1--1 MeV spread can be through controlled injection a slowly expanding bubble arises when particle beam or...
The authors evaluated the use of a new transfer device (roller tray) and compared it with three commonly used devices (slide board, nylon tube, roller board). Caregivers experienced greatest low back stress moving patients weighing 70 to 90 kg (approximately 150 200 lb). Qualitative data overwhelmingly favored tray disposable absorbent underpads over other devices. L4-5 torque not when transferring heaviest (over or approximately lb), but rather those kg. These "middle-weight" are often...
Relative Navigation (RelNav) applications, have been identified as an enabling function of many NASA's future mission architectures, including Rendezvous, Proximity Operations and Docking (RPOD), well planetary surface rendezvous landing, mobility in space servicing. Functional capabilities maintained exercised for decades, but recent design test efforts validated revolutionary improvements functionality performance levels active passive relative navigation sensors processing, providing a...
This paper presents a new method for calculating the cavity modes of cylindrically symmetric cavities and applies to stacked dielectric resonators (DRs) inside conducting cylindrical shell. The an arbitrary are expressed using eigenfunction expansion, basis functions being fields empty cavity. wave equation electric displacement field, D, can be manipulated eliminate derivatives discontinuous constant provide eigenvalue resonant frequencies eigenvectors specify coefficients that sum compose...
A single-point, frequency-domain nonlinearity indicator is calculated and analyzed for noise from a model-scale jet at Mach 0.85, 1.8, 2.0. The indicator, νN, has been previously derived an ensemble-averaged, version of the generalized Burgers equation (GBE) Reichman, Gee, Neilsen, Miller [J. Acoust. Soc. Am. 139, 2505-2513 (2016)]. gives spatial rate change due to nonlinear processes in sound pressure level (SPL) spectrum, two other indicators GBE-νS να-give same quantity geometric...
Abstract Laser wakefield accelerators (LWFAs) have electric fields that are orders of magnitude larger than those conventional accelerators, promising an attractive, small-scale alternative for next-generation light sources and lepton colliders. The maximum energy gain in a single-stage LWFA is limited by dephasing, which occurs when the trapped particles outrun accelerating phase wakefield. Here, we demonstrate single space–time structured laser pulse can be used ionization injection...