A5057406418- Ion-surface interactions and analysis
- Diamond and Carbon-based Materials Research
- Metal and Thin Film Mechanics
- Laser-Plasma Interactions and Diagnostics
- Fusion materials and technologies
- Graphene research and applications
- nanoparticles nucleation surface interactions
- Boron and Carbon Nanomaterials Research
- High-pressure geophysics and materials
- Aerogels and thermal insulation
- Carbon Nanotubes in Composites
- Nanoporous metals and alloys
- Laser-induced spectroscopy and plasma
- Advanced Chemical Physics Studies
- Catalytic Processes in Materials Science
- Supercapacitor Materials and Fabrication
- Quantum Dots Synthesis And Properties
- Semiconductor materials and devices
- Nuclear Physics and Applications
- Nonlinear Optical Materials Studies
- Magnetic confinement fusion research
- Phase-change materials and chalcogenides
- Semiconductor materials and interfaces
- Mesoporous Materials and Catalysis
- Nuclear Materials and Properties
Lawrence Livermore National Laboratory
2015-2024
Lawrence Livermore National Security
2018-2024
Dankook University
2024
General Atomics (United States)
2020-2022
Argonne National Laboratory
2021
Lawrence Berkeley National Laboratory
2008-2016
University of California, Berkeley
2008-2016
An inertial fusion implosion on the National Ignition Facility, conducted August 8, 2021 (N210808), recently produced more than a megajoule of yield and passed Lawson's criterion for ignition [Phys. Rev. Lett. 129, 075001 (2022)]. We describe experimental improvements that enabled N210808 present first measurements from an igniting plasma in laboratory. metrics like product hot-spot energy pressure squared, absence self-heating, increased by ∼35%, leading to record values enhancement...
We present the design of first igniting fusion plasma in laboratory by Lawson's criterion that produced 1.37 MJ energy, Hybrid-E experiment N210808 (August 8, 2021) [Phys. Rev. Lett. 129, 075001 (2022)10.1103/PhysRevLett.129.075001]. This uses indirect drive inertial confinement approach to heat and compress a central "hot spot" deuterium-tritium (DT) fuel using surrounding dense DT piston. Ignition occurs when heating from absorption α particles created process overcomes loss mechanisms...
An indirect-drive inertial fusion experiment on the National Ignition Facility was driven using 2.05 MJ of laser light at a wavelength 351 nm and produced 3.1±0.16 total yield, producing target gain G=1.5±0.1 exceeding unity for first time in laboratory [Phys. Rev. E 109, 025204 (2024)10.1103/PhysRevE.109.025204]. Herein we describe experimental evidence increased drive capsule additional energy control over known degradation mechanisms, which are critical to achieving high performance....
Aerogels are used in a broad range of scientific and industrial applications due to their large surface areas, ultrafine pore sizes, extremely low densities. Recently, number reports have described graphene aerogels based on the reduction oxide (GO). Though these GO-based represent considerable advance relative traditional carbon aerogels, they remain significantly inferior individual sheets poor crystallinity. Here, we report straightforward method synthesize highly crystalline via...
We describe the synthesis and characterization of monolithic, ultralow density WS2 MoS2 aerogels, as well a high surface area MoS2/graphene hybrid aerogel. The monolithic aerogels are prepared via thermal decomposition freeze-dried ammonium thio-molybdate (ATM) thio-tungstate (ATT) solutions, respectively. densities pure dichalcogenide represent 0.4% 0.5% full WS2, respectively, can be tailored by simply changing initial ATM or ATT concentrations. Similar processing in presence graphene...
Porosity generally embrittles ceramics. In contrast to such expectations, this report demonstrates that an effective fracture strain of nanoporous silica aerogels increases with increasing porosity. At ultralow relative densities <0.5%, monoliths start exhibiting super-compressible deformation strains >50%. This is attributed consequences increase in the aspect ratio ligaments decreasing density.
Realization of macroscale three‐dimensional isotropic carbons that retain the exceptional electrical and mechanical properties graphene sheets remains a challenge. Here, method for fabricating graphene‐derived (GDCs) with approaching those individual is reported. This synthesis scheme relies on direct cross‐linking via functional groups in oxide to maximize electronic transport reinforcement between partial restacking increase material density about 1 g cm ‐3 . These GDCs exhibit 3–6 orders...
The synthesis of ultralow-density (>5 mg/cm(3) ) bulk materials with interconnected nanotubular morphology and deterministic, fully tunable feature size, composition, density is presented. A thin-walled design realized by employing templating based on atomic layer deposition makes the material about 10 times stronger stiffer than aerogels same density.
Magnetizing a cryogenic deuterium–tritium (DT)-layered inertial confinement fusion (ICF) implosion can improve performance by reducing thermal conduction and improving DT-alpha in the hot spot. A room-temperature, magnetized indirect-drive ICF platform at National Ignition Facility has been developed, using high-Z, high-resistivity AuTa4 alloy as hohlraum wall material. Experiments show 2.5× increase deuterium–deuterium (DD) neutron yield 0.8-keV hot-spot temperature with application of 12-T...
We report the preparation of low density polymeric aerogels using ring opening metathesis polymerization (ROMP) approach to copolymerize dicyclopentadiene (DCPD) with norbornene-based monomers (NB-R) employing a first generation Grubbs' ruthenium-based catalyst. The ROMP offers an attractive synthetic method that enables fabrication low-density (0.02–0.05 g cm−3), uniform thickness aerogel coatings on non-planar substrates. First, we explore effect crosslinking in polymer backbone uniformity...
Abstract We report on fabrication and characterization of layered, tungsten doped, spherical about 2 mm diameter microcrystalline diamond ablator shells for inertial confinement fusion (ICF) experiments at the National Ignition Facility. As previously reported, ICF can be fabricated by chemical vapor deposition (CVD) solid silicon mandrels using an ellipsoidal microwave plasma reactor. In present work, we further developed these embedding a W -doped layer sandwiched between two undoped...
Phase change materials are essential to a number of technologies ranging from optical data storage energy and transport applications. This widespread interest has given rise substantial effort develop bulk phase well suited for desired Here, we suggest novel complementary approach, the use binary eutectic alloy nanoparticles embedded within matrix. Using GeSn in silica as an example, establish that presence nanoparticle/matrix interface enables one stabilize both nanobicrystal homogeneous...
Abstract Taking full advantage of the unique laboratory environment created by National Ignition Facility (NIF) will require availability foam-lined indirect-drive inertial confinement fusion targets. Here, we report on a new approach that enables fabrication target structures consist thin-walled (<30 µm) ultra-low-density mg cm −3 ) hydrocarbon foam film inside thick-walled, ∼2 mm diameter ablator shell. In contrast to previous work direct-drive targets started with shells, use...
Compared to tedious, multi-step treatments for electroless gold plating of traditional thermoplastics, this communication describes a simpler three-step procedure 3D printed crosslinked polyacrylate substrates. This allows the synthesis ultralight foam microlattice materials with great potential architecture-sensitive applications in future energy, catalysis, and sensing.
Sputter deposition of ultrathick (≈20μm) Au–Ta alloy coatings on sphero-cylindrical substrates is key for the fabrication hohlraums magnetically assisted inertial confinement fusion. Here, we study AuTa4 onto rotating substrates. We use high-power impulse magnetron sputtering (HiPIMS) in a constant peak target voltage mode. Results show that erosion state has strong impact dominant crystallographic phase, microstructure, surface morphology, and electrical resistivity films. This due to...
Sputter deposition of B4C films with tailored physical properties remains a challenge. Here, we systematically study how substrate temperature influences the deposited by direct current magnetron sputtering onto planar substrates held at temperatures in range 100−510°C. Results show that all are amorphous stoichiometric B4C, low O content ∼1 at. %. Films 100°C exhibit high compressive residual stress and decreased mechanical properties. For elevated 180−510°C, film mass density, surface...
The deposition of thick B4C films with low residual stress by conventional direct-current magnetron sputtering is accompanied the formation dust particulates contaminating target, chamber, and substrates leading to nodular defects in films. Here, we demonstrate that greatly reduced during radio-frequency (RFMS). We systematically study properties deposited RFMS a substrate temperature 330 °C, target-to-substrate distance 10 cm, Ar working gas pressure range 4.5–12.0 mTorr (0.6–1.6 Pa), tilt...
Magnetron sputter deposition is an enabling technology for laser target fabrication. Solutions are readily available the of most sub-micron-thick elemental films on planar substrates. However, major challenges still remain development robust processes in regimes ultrathick (over ∼10 μm) coatings and nonplanar These challenging directly relevant to applications, including both sphero-cylindrical hohlraums spherical ablators inertial confinement fusion (ICF) targets. Understanding underlying...
A tunable structural engineering of nanowires based on template-assisted alloying and phase segregation processes is demonstrated. The Au−Ge system, which has a low eutectic temperature negligible solid solubility (<10−3 atom %) Au in Ge at temperatures, utilized. Depending the concentration initial nanowires, final structures ranging from nearly periodic nanodisk patterns to core/shell fully alloyed are produced. formation mechanisms discussed detail characterized by situ transmission...
Abstract Gold–tantalum alloy films are attractive for hohlraums used in indirect drive magnetized inertial confinement fusion. A high electrical resistivity of over ∼100 µ Ω cm at cryogenic temperatures is an essential requirement allowing externally imposed pulsed magnetic field to soak through a hohlraum and magnetize the fusion fuel. Here, we systematically study properties Au–Ta entire compositional range from pure Au Ta with thicknesses up 30 m. These made by direct current magnetron...