EXTENDING CROSSED-FIELD DEVICE PHYSICS
Abstract
The primary goal of this project is to combine theory, simulation, and experiment to elucidate crossed-field device (CFD) physics and improve the performance of CFDs such as magnetrons, crossed-field amplifiers (CFAs), and magnetically insulated transmission line oscillators (MILOs). These improvements could include magnetron phase control by injection locking, fast magnetron start-up, reduced noise in CFAs, and improved CFA gain. Our approach includes the study of fundamental crossed-field physics such as the transition from cycloidal to Brillouin flow, which remains a topic of theoretical investigation; the mechanism for the start-up of magnetrons including diocotron instabilities; and the generation and propagation of noise. The team will extend theoretical developments, simulations, and experiments from our prior work. Experiments will use gated field emission arrays as an electron source for a linear format L-band, 500 W CFA to study gain and noise with electron modulation; an L-band industrial magnetron (CWM75kW) operating at low power (1 kW) to study magnetron startup and phase using a modulated electron source; a coaxial crossed-field structure to study the transition to Brillouin flow and instabilities; and a cylindrical format, L-band CFA (500 W) to study gain and noise propagation. The CFAs and coaxial structures will use segmented collectors and in-situ probes to measure the electron density, energy distribution, and RF fields. A new generation of high frequency (2 GHz), reliable, high current density (100 A/cm2) gated field emission arrays (GFEAs) will be developed. All devices will be simulated using a particle-in-cell code, and the simulations and experiments will be compared with existing and newly developed theories for generalized geometries for space charge limited current and the transition to Brillouin flow in CFDs. Theory will also be extended to crossed-field gaps with interaction circuits.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 20, 2023
- Source ID
- FA95502210434
Entities
People
- Jim Browning
Organizations
- Air Force Office of Scientific Research
- Boise State University
- United States Air Force