High Current, High Brightness Ferroelectric Electron Source

HIGH CURRENT, HIGH BRIGHTNESS ADVANCED ELECTRON BEAM SOURCES ARE REQUIRED FOR DIRECTED ENERGY EXPERIMENTS AND COMMERCIAL APPLICATIONS WHICH INCLUDE FREE ELECTRON LASERS, HIGH POWER MICROWAVES, ELECTRON BEAM PUMPED LASERS AND MICROWAVE SOURCES FOR COMMUNICATIONS, PLASMA PROCESSING AND ACCELERATOR SYSTEMS. PRESENT SOURCES SUCH AS THERMIONIC AND PHOTOCATHODES ARE LIMITED BY CURRENT DENSITY, TOTAL CURRENT AND ARE COMPLEX DUE TO HIGH VACUUM, AND LASER REQUIREMENTS. WE PROPOSE A HIGH CURRENT, HIGH BRIGTHNESS CATHODE BASED ON EMISSION FROM FERROELECTRIC MATERIALS. FERROELECTRIC CATHODES OPERATE AT ROOM TEMPERATURE USING SPONTANEOUSLY POLARIZED MATERIALS SUCH AS LEAD TITANATE- ZIRCONATE. PREVIOUS RESEARCH AT CERN, CORNELL AND INTEGRATED APPLIED PHYSICS HAS DEMONSTRATED THESE CATHODES TO PRODUCE HIGH CURRENT DENSITY, HIGH QUALITY ELECTRON BEAMS. ELECTRON EMISSION OCCURS UPON POLARIZATION CHANGE INDUCED BY A FAST ALMOST 20 KV/CM PULSE APPLIED TO THE MATERIAL. OUR PREVIOUS RESEARCH HAS INDICATED HIGH BRIGTHNESS, >10(11) A/M(2)RAD(2) PERFORMANCE OPERATING AT PRESSURES AS HIGH AS 10 (-3) TORR. ROOM TEMPERATURE EMISSION OF ELECTRONS COMBINED WITH HIGH CURRENT CAPABILITY, SEVERAL 100 A/CM(2), GIVEN THE POSSIBILITY OF BEAMS WITH BRIGHTNESS >10(12) A/M(2)RAD(2) WHICH EXCEEDS PRESENT PHOTOCATHODES. DURING PHASE I, WE PROPOSE TO DEMONSTRATE THE SOURCE AND DETERMINE THE BRIGTHNESS CAPABILITY AT KILO-AMPERE PEAK CURENTS. DURING PHASE II, A COMMERICAL DEVICE WILL BE DEVELOPED FOR DEFENSE AND INDUSTRIAL APPLICATIONS.