A5028037865- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Advanced X-ray Imaging Techniques
- Gyrotron and Vacuum Electronics Research
- Nuclear Physics and Applications
- Nuclear physics research studies
- Superconducting Materials and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Particle Detector Development and Performance
- Advanced Electron Microscopy Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- Radiation Detection and Scintillator Technologies
- Advancements in Photolithography Techniques
- Quantum Chromodynamics and Particle Interactions
- Laser-Plasma Interactions and Diagnostics
- Particle physics theoretical and experimental studies
- Atomic and Molecular Physics
- Advanced Surface Polishing Techniques
- Photonic and Optical Devices
- Advanced Data Storage Technologies
- Photocathodes and Microchannel Plates
- High-Energy Particle Collisions Research
- Advanced X-ray and CT Imaging
- Adaptive optics and wavefront sensing
- Orbital Angular Momentum in Optics
Shanghai Jiao Tong University
2024
Duke University
2015-2024
Triangle Universities Nuclear Laboratory
2015-2024
Stony Brook University
2023
Laser Zentrum Hannover
2021
North Carolina Central University
2021
Xi'an Aeronautical University
2021
University of Padua
2020
National Astronomical Observatories
2019
University of Chinese Academy of Sciences
2019
Layered and cathodes belonging to the solid solution series between have been synthesized characterized by charge-discharge measurements in lithium cells before after modifying their surface with . The surface-modified show significantly lower irreversible capacity loss (ICL) higher discharge excellent cyclability compared unmodified counterparts. For example, modified shows a remarkably high of an ICL good rate capability. This value is much than that achieved previously known similar modification
A nearly monochromatic beam of 100% linearly polarized γ rays has been produced via Compton backscattering inside a free electron laser optical cavity. The 12.2 MeV was obtained by 379.4 nm free-electron photons from 500 electrons circulating in storage ring. detailed description the γ-ray and outlook for future improvements are presented.Received 24 February 1997DOI:https://doi.org/10.1103/PhysRevLett.78.4569©1997 American Physical Society
The second J(π)=2+ state of 12C, predicted over 50 years ago as an excitation the Hoyle state, has been unambiguously identified using 12C(γ,α0)(8)Be reaction. alpha particles produced by photodisintegration 12C were detected optical time projection chamber. Data collected at beam energies between 9.1 and 10.7 MeV intense nearly monoenergetic gamma-ray beams HIγS facility. measured angular distributions determine cross section E1-E2 relative phases a function energy leading to unambiguous...
Directed self-assembly (DSA) of block copolymers (BCPs), either by selective wetting surface chemical prepatterns or graphoepitaxial alignment with topography, has ushered in a new era for high-resolution nanopatterning. These pioneering approaches, while effective, require expensive and time-consuming lithographic patterning each substrate to direct the assembly. To overcome this shortcoming, nanoimprint molds—attainable via low-cost optical lithography—were investigated their potential be...
Compton scattering of a laser beam with relativistic electron has been used to generate intense, highly polarized and nearly monoenergetic x-ray or gamma-ray beams at many facilities. The ability predict the spatial, spectral temporal characteristics is crucial for optimization operation light source as well applications utilizing beam. In this paper, we present two approaches, one based upon analytical calculations other Monte Carlo simulations, study process various parameters different...
Objective: To establish an inductively coupled plasma mass spectrometry (ICP-MS) method for the rapid determination of total bromine in whole blood, and to provide technical support monitoring exposure occupational populations. Methods: In September 2023, 0.25 ml blood sample was added with 0.25% tetramethylammonium hydroxide solution a volume 5.0 ml, ultrasonicated homogenized, then quantified by ICP-MS rhodium as online internal standard solution. Results: The linear relationship good...
Abstract The SiTian project, designed to utilize 60 telescopes distributed across multiple sites in China, is a next-generation time-domain survey initiative. As pathfinder of the mini (MST) has been proposed and implemented test brain, data pipeline, evaluate feasibility its technology science cases. Mounted at Xinglong Observatory, MST project comprised three 30 cm operated since Nov. 2022. Each telescope possesses large field view, covering 2.29° × 1.53° FOV, mounted g', r', i' filters,...
Plasma etching is a powerful technique for transferring high-resolution lithographic masks into functional materials. Significant challenges arise with shrinking feature sizes, such as thin masks. Traditionally this has been addressed hard and consequently additional costly steps. Here we present pathway to high selectivity soft mask pattern transfer using cryogenic plasma towards low-cost throughput sub-10 nm nanofabrication. Cryogenic SF6/O2 gas chemistry studied fidelity, inductively...
This Letter reports the first experimental results from world's distributed optical-klystron (DOK) free-electron laser (FEL), DOK-1 FEL, at Duke University. The FEL is a hybrid system, comprised of four wigglers: two horizontal and helical. With we have obtained highest gain among all storage ring based FELs 47.8% (+/-2.7%) per pass. We also demonstrated that can be enhanced by increasing electron bunching using wigglers with different polarization. Furthermore, realized controlled...
The mixing ratios of $M1$ and $E2$ radiation for transitions in $^{11}\mathrm{B}$ have been determined by measuring the azimuthal asymmetry emitted from levels populated resonant absorption polarized photons. photon-scattering experiments were carried out at Free-Electron Laser Laboratory Duke University using nearly monoenergetic linearly photon beams. deduced a comparison measured asymmetries with calculations angular distributions mixed transitions.
A step and repeat UV nanoimprint lithography process on pre-spin coated resist film is demonstrated for patterning a large area with features sizes down to sub-15 nm. The high fidelity between the template imprinted structures verified difference in their line edge roughness of less than 0.5 nm (3σ deviation value). pattern's residual layer well controlled allow direct pattern transfer from into functional materials very resolution. suitable fabricating numerous nanodevices.
There are two X-ray technologies which very useful for probing the electrode microstructure and atomic structure of material in lithium ion batteries, namely absorption spectroscopy tomography. This article introduces history provides a description these techniques, highlights their advantages disadvantages. XAS tomography proven to be powerful tools determining electronic materials. In combination with other advanced methodologies, methods can engender great advance fundamental...
Abstract A workshop on The Next Generation Gamma-Ray Source sponsored by the Office of Nuclear Physics at Department Energy, was held November 17-19, 2016 in Bethesda, Maryland. goals were to identify basic and applied research opportunities frontiers nuclear physics that would be made possible beam capabilities an advanced laser Compton facility. To anchor scientific vision realistically achievable specifications using proven technologies, brought together experts fields electron...
We report first results from our effort to couple a high resolution photoemission electron microscope (PEEM) the OK-4 ultraviolet free laser at Duke University (OK-4/Duke UV FEL). The OK-4/Duke FEL is intensity source of tunable monochromatic photons in 3–10 eV energy range. This tunability unique and allows us operate near threshold any samples thus maximize sample contrast while keeping chromatic berrations PEEM minimal. have recorded images variety using spontaneous radiation OK-4/ photon...
This Letter reports the first observations of an anomalous hollow electron beam in Duke storage ring. Created by exciting single-bunch a lattice with negative chromaticity, consists solid core inside and large ring outside. We report detailed measurements phenomenon, including its distinct image pattern, spectrum signature, evolution time. By capturing postinstability bursting beam, is unique model system for studying transverse instabilities, particular, interplay wakefield nonlinearity. In...
Particle motion in storage rings is confined by various aperture limits, the size of which restricts performance ring terms injection efficiency, lifetime, etc. Intrabeam scattering makes particles sweep a large portion phase space, where their may eventually be resonantly or chaotically excited to amplitudes leading collision with vacuum chamber. We report here studies performed at Advanced Light Source (ALS) on on- and off-momentum particle that provides good understanding these...
A new ultrahigh-resolution photoemission electron microscope called PEEM3 is being developed at the advanced light source (ALS). An mirror combined with a sophisticated magnetic beam separator used to provide simultaneous correction of spherical and chromatic aberrations. Installed on an elliptically polarized undulator beamline, will be operated very high spatial resolution flux study composition, structure, electric properties complex materials.
This paper reports our recent work on explicit symplectic integration techniques for the charged particle motion in an s-dependent static magnetic field. Using extended phase space, integrators can be developed Hamiltonians with or without paraxial approximation using either space time as independent variable. extends successful element-by-element tracking method studying single-particle nonlinear dynamics to a set of elements. Important applications this include studies storage ring various...
A gamma-ray beam produced by Compton scattering of a laser with an electron can be used to measure the parameters. In several published works, simple fitting model has been applied determine energy and spread without considering gamma collimation emittance effects. This is rederived in this work, underlying assumptions resultant limitations are discussed. To overcome these limitations, new proposed, which takes into account Using at high intensity $\ensuremath{\gamma}$-ray sources facility...
Based on the scattering matrix method, we theoretically demonstrate that chiral interaction can induce almost perfect photon blockade (PB) in waveguide-cavity quantum electrodynamics (QED) system. The mechanism relies multi-photon-paths interference within waveguide, which is clearly shown by analytical parameter regime for $g^{(2)}(0)\approx0$. When $N$ cavities are introduced into system, there optimal points accordingly PB, and required chirality decreases exponentially with increasing...