Imaging atomically thin transition metal dichalcogenides using deep ultraviolet photoelectron emission microscopy.
Abstract not provided.
Boehm, Alexander↗
Engineering topics
Thomas, Cherrelle
Publications and source records attributed to Thomas, Cherrelle.
Progress in micron-scale field emission models based on nanoscale surface characterization for use in PIC-DSMC vacuum arc simulations.
Abstract not provided.
Moore, Christopher↗
Employing Nanoscale Surface Characterizations in a Field Emission Model.
Abstract not provided.
Hopkins, Matthew M.↗
AMPPED LDRD: Advanced Models of the Physics & Phenomena of Electrical Discharge.
This Laboratory Directed Research and Development (LDRD) project aimed at addressing an unmet need for physics-based models that enable prediction of electrical breakdown in the presence of high voltage gradients and real-world environments. This project focused on understanding coupled plasma-surface feedback phenomena critical to electrical discharge processes and design of breakdown voltages, breakdown times, and breakdown paths. New secondary electron emission and coupled plasma-surface measurement methods and models were developed. Highly reproducible discharge experiments were developed to provide current-voltage data as a function of time, and methods were developed to condition electrodes for predictable discharge. To assess plasma-surface feedback mechanisms, new surface physics capabilities, including measurement systems for local and global photoemission yield and ion-induced secondary electron emission yield were developed. Discharge models were developed to incorporate these yields for predicting discharge behavior to understand influence of surface physics on discharge current and time evolution, and methods to accelerate these simulations were demonstrated. A key finding was that the initiation process of a non-vacuum discharge appears highly dependent on photoemission at the cathode. Advanced diagnostics were developed, including spatial electrical field imaging, spectroscopy of plasmas, and high-speed imaging of discharge event s in metal and dielectric environments. These diagnostics and improved electrical models are a step toward enabling quantitative design margins, assurance of safety architectures, and implementation of novel materials and technologies for wide ranging energy and electronics applications.
70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗