A5081842254- Ga2O3 and related materials
- ZnO doping and properties
- Nuclear physics research studies
- Electronic and Structural Properties of Oxides
- Atomic and Molecular Physics
- Particle physics theoretical and experimental studies
- Advanced Photocatalysis Techniques
- Semiconductor materials and devices
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Thermal Expansion and Ionic Conductivity
- Gamma-ray bursts and supernovae
- Electromagnetic Simulation and Numerical Methods
- Nuclear Physics and Applications
- Neutrino Physics Research
- Astronomical and nuclear sciences
- Astro and Planetary Science
- Magnesium Oxide Properties and Applications
- Thermal properties of materials
- Electromagnetic Scattering and Analysis
- Magnetic and transport properties of perovskites and related materials
- Multiferroics and related materials
- Orbital Angular Momentum in Optics
- Lightning and Electromagnetic Phenomena
- Astronomical Observations and Instrumentation
Wright-Patterson Air Force Base
2020-2021
U.S. Air Force Research Laboratory Sensors Directorate
2020-2021
United States Air Force Research Laboratory
2020-2021
National Academies of Sciences, Engineering, and Medicine
2020
Michigan State University
2013-2019
National Superconducting Cyclotron Laboratory
2013-2017
Joint Institute for Nuclear Astrophysics
2015
The lattice thermal conductivity for bulk β-Ga2O3 is computed from the phonon Boltzmann transport equation using first-principles methods to obtain scattering rates. Force constants both second and third order potential interactions are with a real-space finite-displacement approach. Phonon band structures as well anharmonic properties then used calculate tensor κ, temperatures ranging 25 K 1050 K. calculated components analytic fits their temperature dependences elaborated. We compare our...
Heteroepitaxy of β-phase gallium oxide (β-Ga2O3) thin films on foreign substrates shows promise for the development next-generation deep ultraviolet solar blind photodetectors and power electronic devices. In this work, influences film thickness crystallinity thermal conductivity (2̅01)-oriented β-Ga2O3 heteroepitaxial were investigated. Unintentionally doped grown c-plane sapphire with off-axis angles 0° 6° toward ⟨112̅0⟩ via metal–organic vapor phase epitaxy (MOVPE) low-pressure chemical...
Classical novae are expected to contribute the 1809-keV Galactic $\gamma$-ray emission by producing its precursor $^{26}$Al, but yield depends on thermonuclear rate of unmeasured $^{25}$Al($p,\gamma$)$^{26}$Si reaction. Using $\beta$ decay $^{26}$P populate key $J^{\pi}=3^+$ resonance in this reaction, we report first evidence for observation exit channel via a $1741.6 \pm 0.6 (\textrm{stat}) 0.3 (\textrm{syst})$ keV primary $\gamma$ ray, where uncertainties statistical and systematic,...
Background: Measurements of $\beta$ decay provide important nuclear structure information that can be used to probe isospin asymmetries and inform astrophysics studies. Purpose: To measure the $\beta$-delayed $\gamma$ $^{26}$P compare results with previous experimental shell-model calculations. Method: A fast beam produced using fragmentation was implanted into a planar germanium detector. Its $\gamma$-ray emission measured an array 16 high-purity detectors. Positrons emitted in were...
Background: The Doppler broadening of $\gamma$-ray peaks due to nuclear recoil from $\beta$-delayed nucleon emission can be used measure the energies nucleons. This method has never been tested using proton or applied a heavier than $A=10$. Purpose: To test and apply this $^{26}$P($\beta p\gamma$)$^{25}$Al decay sequence. Methods: A fast beam $^{26}$P was implanted into planar Ge detector, which as $\beta$-decay trigger. SeGA array high-purity detectors detect $\gamma$ rays Results:...
We study the electrical and optical properties of degenerate ZnGa2O4 films grown by metalorganic chemical vapor deposition (MOCVD) on sapphire semi-insulating pulsed laser (PLD) fused silica. After a forming-gas anneal at 700 °C, MOCVD film is highly conducting, with room-temperature carrier concentration 2 × 1020 cm−3, mobility 20 cm2/V s, direct bandgap absorptions 3.65 eV 4.60 eV. Under same annealing conditions, PLD semi-insulating, absorption 5.25 The phonon structure, important for...
We show that the present approaches for solution of Maxwell’s equations in complex geometries have limitations can be overcome through use C(1)-continuous Hermite interpolation polynomials. Our approach calculating fields using finite element method yields better accuracy by several orders magnitude than comparable applications edge-based vector method. note is widely used pixelated solutions and ill-defined at nodes. a smooth representation within across elements well defined directions...
We report the independent experimental confirmation of an isomeric state in proton drip-line nucleus $^{26}\mathrm{P}$. The $\ensuremath{\gamma}$-ray energy and half-life determined are $164.4\ifmmode\pm\else\textpm\fi{}0.3\phantom{\rule{0.16em}{0ex}}(\text{sys})\ifmmode\pm\else\textpm\fi{}0.2\phantom{\rule{0.16em}{0ex}}(\text{stat})$ keV $104\ifmmode\pm\else\textpm\fi{}14$ ns, respectively, which agreement with previously reported values. These values used to set a semiempirical limit on...
Classical novae are common thermonuclear explosions in the Milky Way galaxy, occurring on surfaces of white-dwarf stars that accreting hydrogen-rich material from companion stars. Nucleosynthesis classical depends radiative proton-capture reaction rates radioactive nuclides. Many these reactions cannot be measured directly at current accelerator facilities due to lack intense, high-quality, radioactive-ion beams relevant energies. Since most proceed via resonant capture, their can determined...
Recent developments in growing highly n-doped wide bandgap oxides such as β-gallium oxide (β − Ga2O3) and more recently zinc gallate (ZnGa2O4) have opened avenues toward important applications, transparent electrodes ohmic contacts. Magnetoconductivity measurements provide a unique method to assess the contribution of phonons mobility over range temperatures. For β Ga2O3 ZnGa2O4, initial attempts interpret measured magnetoconductivity raised fundamental questions about interplay between...
Abstract Disorder arising from random locations of charged donors and acceptors introduces localization diffusive motion that can lead to constructive electron interference positive magnetoconductivity. At very low temperatures, 3D theory predicts the magnetoconductivity is independent temperature or material properties, as verified for many combinations thin-films substrates. Here, we find this prediction apparently violated if film thickness d less than about 300 nm. To investigate origin...
Observation across the Milky Way of a 1809-keV γ-ray characteristic 26 Al decay provides direct evidence for ongoing nucleosynthetic production Al.Although massive stars and supernovae are likely to be primary sites production, classical novae may also contribute significant portion total amount Galactic Al.At peak nova temperatures approximately 0.4 GK, rate 25 Al(p,γ) Si reaction, which bypasses therefore places an upper limit on contributed by abundances, is dominated single 3 +...
We investigate the effects of including full three-loop QCD correction to static short distance $1/r$ potential on spectroscopy and decays in charmonium upsilon systems. use a variational technique with corrected determine set unperturbed trial wave functions treat relativistic one-loop corrections as perturbations. The perturbed results are compared subset spectra using $χ^2$ test. This approach more accurate descriptions hyperfine splittings both $b\bar{b}$ $c\bar{c}$