Coherent photoelectron bunch generation and quantum efficiency enhancement in a photocathode optical resonator

Journal Article · Mon Nov 07 04:00:00 EST 1994 · Applied Physics Letters; (United States)

DOI:https://doi.org/10.1063/1.112689· OSTI ID:6949377

Hartemann, F V; Fochs, S N; McNally, J D; Burns, S; Luhmann, Jr, N C ^[1]; Perry, M D ^[2]; Chu, K R ^[3]

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1. Department of Applied Science, University of California, Davis, California 95616 (United States)
2. Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)
3. Department of Physics, National Tsing Hua University, Hsinchu (Taiwan)

A novel scheme producing multiple, coherently phased, high charge (nC), short duration (ps) electron bunches in a radio-frequency (rf) photoinjector is presented. In this configuration, the mirror photocathode is an integral part of an optical resonator. The ultrashort laser pulse is reflected off the photocathode and recirculated through the optical cavity at a subharmonic of the rf drive frequency after extracting a photoelectron bunch. This new technique can dramatically increase the effective quantum efficiency of metals and produce high current, high brightness, prebunched electron beams ideally suited for high power coherent microwave generation. A proof-of-principle experiment operating at 0.250 GHz and using a frequency-quadrupled, mode-locked Nd:YAG laser has shown the production of a train of coherently phased photoelectron bunches, with a measured effective quantum efficiency enhancement of 4.2.

• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6949377
• Journal Information: Applied Physics Letters; (United States), Journal Name: Applied Physics Letters; (United States) Vol. 65:19; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

661220* -- Particle Beam Production & Handling
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BEAMS
CATHODES
COHERENT PRODUCTION
DESIGN
EFFICIENCY
ELECTRODES
ELECTROMAGNETIC RADIATION
ELECTRON BEAMS
FREE ELECTRON LASERS
INTERACTIONS
LASER CAVITIES
LASER RADIATION
LASERS
LEPTON BEAMS
PARTICLE BEAMS
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PHOTOCATHODES
PULSES
RADIATIONS
Ta
Targets-- (1992-)