A5091589343- Fusion materials and technologies
- Nuclear Materials and Properties
- Nuclear Physics and Applications
- Ion-surface interactions and analysis
- Quantum Chromodynamics and Particle Interactions
- Magnetic confinement fusion research
- Metal and Thin Film Mechanics
- High-Energy Particle Collisions Research
- Particle physics theoretical and experimental studies
- Nuclear reactor physics and engineering
- Nuclear physics research studies
- Plasma Diagnostics and Applications
- Diamond and Carbon-based Materials Research
- Radiation Detection and Scintillator Technologies
- Electronic and Structural Properties of Oxides
- Nuclear materials and radiation effects
- Semiconductor materials and devices
- Superconducting Materials and Applications
- Particle Detector Development and Performance
- High-Temperature Coating Behaviors
- Catalytic Processes in Materials Science
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced materials and composites
- Particle accelerators and beam dynamics
- Radiation Therapy and Dosimetry
Massachusetts Institute of Technology
2015-2025
Plasma Technology (United States)
2015-2024
Fusion Academy
2013-2024
Fusion (United States)
2015-2024
IIT@MIT
2024
United Kingdom Atomic Energy Authority
2021
Culham Science Centre
2021
Oak Ridge National Laboratory
2021
Universität Hamburg
1993-2006
Hermes Arzneimittel (Germany)
2001
Exsolution synthesizes self-assembled metal nanoparticle catalysts via phase precipitation. An overlooked aspect in this method thus far is how exsolution affects the host oxide surface chemistry and structure. Such information critical as itself can also contribute to overall catalytic activity. Combining X-ray electron probes, we investigated transformation of thin-film SrTi0.65Fe0.35O3 during Fe0 exsolution. We found that generates a highly Fe-deficient near-surface layer about 2 nm...
Time-modulated helium (He) ion energy (e.g. VBias = −50 + 25·sin(2πfRF · t), fRF 13.56 MHz) is demonstrated to strongly affect the development of tungsten (W) surface morphology that results from He plasma irradiation in DIONISOS linear experiment. Nano-tendril bundles (NTBs), which appear as isolated 'islands' nano-tendrils, can rapidly grow on an otherwise smooth W surface. This contrast previously seen full-surface coverage nano-tendril growth known 'fuzz'. When tall NTBs form, less than...
The effects of ionizing radiation on materials often reduce to "bad news." Radiation damage usually leads detrimental such as embrittlement, accelerated creep, phase instability, and radiation-altered corrosion. This last point merits special attention. Elucidating synergies between corrosion has been one the most challenging tasks impeding deployment advanced reactors, stemming from combined high temperature, corrosive coolants, intense particle fluxes. Here we report that proton...
A facility for the investigation of in situ radiation-materials and plasma-materials interaction is demonstrated with tungsten, using transient grating spectroscopy as a probe thermal diffusivity surface acoustic wave speed. Helium plasma exposure at 645 °C to 1.18 × 1018 cm−2 helium, until growth tungsten fuzz, showed an increase speed near-surface from 2542 ± 1 m s−1 up 2565 s−1, followed by greater drop 2499 7 s−1. No observable change was present alone. separate 10.26 MeV...
Excitation functions of proton-proton elastic scattering cross sections have been measured in narrow steps for projectile momenta ${p}_{p}$ (energies ${T}_{p}$) from $1100$ to $3300\mathrm{MeV}/c$ (500 2500 MeV) the angular range $35\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}{\ensuremath{\Theta}}_{\mathrm{c}.\mathrm{m}.}\ensuremath{\le}90\ifmmode^\circ\else\textdegree\fi{}$ with a detector providing...
In this research, we highlight ion beam irradiation as an effective external stimulus for precisely tuning the size, density, composition, and spatial distribution of exsolved nanoparticles within a wide range oxide materials.
A major impediment towards a better understanding of the complex plasma-surface interaction is limited diagnostic access to material surface while it undergoing plasma exposure. The Dynamics ION Implantation and Sputtering Of Surfaces (DIONISOS) experiment overcomes this limitation by uniquely combining powerful, non-perturbing ion beam analysis techniques with steady-state helicon exposure chamber, allowing for real-time, depth-resolved in situ measurements compositions during Design...
The speed-up of radiation science development with the advent ion-irradiation experiments has, until recently, been omitted in post-irradiation examination technique. This paper reports results transient grating spectroscopy—a rapid, non-destructive, situ photothermal surface technique—of ion-irradiated single-crystals iron, chromium, vanadium, and tungsten at room temperature. Thermal diffusivity was used to track damage throughout irradiation, 5 MeV self-ion irradiated vanadium showing...
Superconducting magnets based on Rare Earth Barium Copper Oxides (REBCO) offer transformative capabilities in the fields of fusion energy, high energy physics, and space exploration. A challenge shared by these applications is limited lifetime REBCO due to radiation damage sustained during operation. Here we present a new ion-beam facility that enables simultaneous cryogenic irradiation situ characterization commercial tapes. The ion source provides spatially uniform fluxes up 1018...
Future space telescopes, especially X-ray will require thin mirrors to achieve high optical throughput. Thin are more difficult fabricate than thick mirrors, but recent advances have made accurate fabrication of possible. However, must a reflective coating, which typically has non-repeatable and non-uniform intrinsic stress that deforms mirror. Reducing coating by controlling deposition parameters reduces reflectivity. Non-uniform integrated compensation (NISC) methods, in spatially...
The DIONISOS experiment is used to study the impact of RF helium (He) plasma on surface morphology tungsten (W) at a frequency 13.56 MHz. Helium ion energy distributions with span 70–75 eV, while still below sputtering threshold result in nano-tendril bundles (NTBs) and free-standing W whiskers surfaces 1020 K. NTBs are distributed intragranularly coverage less than 10% reaching up 30 µm normal for He fluence 7.6 × 1025 m−2 flux density 1022 s−1. Analysis NTB interior sub-surface structure...
The nearly infinite compositional design space of high entropy alloys (HEAs) presents many opportunities to improve performance in extreme environments, particularly for nuclear reactors. ability some HEAs resist amounts radiation damage, while well documented, has not yet been fully exploited. We studied the irradiation effect different ions (Si and Ni) on microstructure mechanical properties Al0.5CoCrFeNi alloy at its equilibrium state, individual response each phase irradiation. results...
The Liquid Immersion Blanket: Robust Accountancy (LIBRA) experiment will be a first-of-a-kind to explore and develop the liquid immersion blanket (LIB) concept. LIB is radically simple molten–LiF-BeF2 (FLiBe)–salt tritium breeding for deuterium-tritium (D-T)–fueled fusion power plants (FPPs) achieving high ratio (TBR) in neutronics models. However, FLiBe inherently difficult study experimentally. As result, coupled issues of radiochemistry (T) transport are poorly understood. LIBRA...
Recent research on the Alcator C-Mod tokamak has focused a range of scientific issues with particular emphasis ITER needs and detailed comparisons between experimental measurements predictive models. Research ICRF (ion cyclotron frequencies) heating emphasized origins mitigation metallic impurities while work lower hybrid current drive experiments have linear nonlinear wave interactions that limit efficiency at high densities in regimes low single pass absorption. Experiments core turbulence...
Quinary GaInAsSbBi is grown by molecular beam epitaxy, and the alloy demonstrated with a bandgap energy of 291 meV (λcutoff ∼ 4.3 μm) minority carrier lifetime 0.34 μs at 120 K. The epilayer to thickness 1 μm 400 °C lattice-matched GaSb substrate Bi mole fraction 0.13% measured Rutherford backscattering spectroscopy. Steady-state time-resolved photoluminescence measurements are performed gauge comparative bandgaps optical quality as well InAsSbBi GaInAsSb reference samples. A recombination...