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OALV design with High-k Photoconductor and High-k Optical Window

LLNL researchers has developed designs to augment WBG/UWBG-based OALVs to improve their power handling capability under CW operational environments.  These designs include:

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Segments of transmission line lengths can be switched to open circuit (as shown) or shorted to the ground (not shown)

Design and construction of a photoconductive switch requires a diamond photoconductor illuminated by light of a certain excitation wavelength.  The diamond material is specifically doped with substitutional nitrogen, which act as a source of electrons.  The device architecture allows maximum light entering the aperture.  The top and bottom electrodes are made of ultra wide band gap (UWBG)…

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Annular illumination on photo conductor by Conical Total Internal Reflection “CTIR” endcap

The approach is to use a custom-designed frustrum and attach it to the optical fiber that connects to the PCSS.  Light from the fiber enters the frustrum, spreads out, and enters the PCSS.  Any unabsorbed light re-enters the frustrum and, because of its geometry, reflects back into the PCSS itself with only a negligible fraction escaping from the fiber.  The shape of the novel frustrum is…

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Plasma wind
CRETIN is a 1D, 2D, and 3D non-local thermodynamic equilibrium (NLTE) atomic kinetics/radiation transport code which follows the time evolution of atomic populations and photon distributions as radiation interacts with a plasma consisting of an arbitrary mix of elements. It can provide detailed spectra for comparing with experimental diagnostics.
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Intrinsic Use Control

LLNL's method of equivalent time sampling incorporates an embedded system that generates the pulses used to trigger the external circuit and the data acquisition (DAQ). This removes the external reference clock, allowing the overall system clock rate to change based on the ability of the embedded system. The time delays needed to create the time stepping for equivalent time sampling is done by…

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Toy model demonstration of a Napier Deltic Engine. Thermo-structural analysis in Diablo with piston pressure. Simrev software-twin is seven python modules; pistons, crank-arms, gears, etc.; and a main program. Total 600 lines of code.

Simrev is a python library imported into a user-generated program. As the program grows in capability and complexity, the engineered product matures. The "software twin" handles all changes to product configuration and is the portal to running supercomputing analysis and managing workflow for engineering simulation codes. Assemblies become program modules; parts, materials, boundary conditions…

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OTV Image

The Optical Transconductance Varistor (OTV, formerly Opticondistor) overcomes depletion region voltage limitations by optically exciting wide bandgap materials in a compact package. A 100μm thick crystal could have the capability approaching 40kV and would replace numerous equivalent junction devices. Thus, unlike present junction transistors or diodes, this wide bandgap device can be stacked…