A thyristor will stay conducting until the current through the device is zero (“current zero”) or perhaps slightly negative. LLNL’s approach is to use the opticondistor (“OTV”) to force this current zero in order to force the device into an “off” state. By combining a light-activated thyristor with an OTV, a noise-immune, high efficiency, high-power switching device can be constructed. The…
Image
The approach is to leverage the fact that a momentary “load” equal to the power transmission line impedance, (Z0), during the transient can suppress its propagation. Z(0) is typically a fixed impedance of several hundred ohms based on the geometry of most single wire transmission lines.
So, an isolated self-powered opticondistor (OTV) system may provide an ultrafast method of…
Image
Improving the active material of the Zn anode is critical to improving the practicality of Zn-MnO2 battery technology. LLNL researchers have developed a new category of 3D structured Zn anode using a direct-ink writing (DIW) printing process to create innovative hierarchical architectures. The DIW ink, which is a gel-based mixture composed of zinc metal powder and organic binders, is extruded…
Image
LLNL’s novel approach utilizes a number of techniques to improve reconstruction accuracy:
Image
Versatile Cold Spray (VCS) enables deposition of brittle materials, such as thermoelectrics, magnets, and insulators, while retaining their functional properties. Materials can be deposited on substrates or arbitrary shapes with no requirement to match compositions. The VCS system is low cost, easily portable, and easy to use.
VCS has been developed in a collaboration between Lawrence Livermore…
Image
Recent advancements in additive manufacturing, also called 3D printing, allow precise placement of materials in three dimensions. LLNL researchers have invented mechanical logic gates based on flexures that can be integrated into the microstructure of a micro-architected material through 3D printing. The logic gates can be combined into circuits allowing complex logic operations to be…
Image
LLNL pioneered the use of tomographic reconstruction to determine the power density of electron beams using profiles of the beam taken at a number of angles. LLNL’s earlier diagnostic consisted of a fixed number of radially oriented sensor slits and required the beam to be circled over them at a fixed known diameter to collect data. The new sensor design incorporates annular slits instead,…
Image
The LLNL method for optimizing as built optical designs uses insights from perturbed optical system theory and reformulates perturbation of optical performance in terms of double Zernikes, which can be calculated analytically rather than by tracing thousands of rays. A new theory of compensation is enabled by the use of double Zernikes which allows the performance degradation of a perturbed…