Author: Korman, C.E.
Paper Title Page
TUPPD083 Raising Photoemission Efficiency with Surface Acoustic Waves 1596
 
  • A. Afanasev, F. Hassani, C.E. Korman
    GWU, Washington, USA
  • V.G. Dudnikov, R.P. Johnson
    Muons, Inc, Batavia, USA
  • M. Poelker, K.E.L. Surles-Law
    JLAB, Newport News, Virginia, USA
 
  Funding: Supported in part by DOE STTR Grant DE-SC0006256. Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177
We are developing a novel technique that may help increase the efficiency and reduce costs of photoelectron sources used at electron accelerators. The technique is based on the use of Surface Acoustic Waves (SAW) in piezoelectric materials, such as GaAs, that are commonly used as photocathodes. Piezoelectric fields produced by the traveling SAW spatially separate electrons and holes, reducing their probability of recombination, thereby enhancing the photoemission quantum efficiency of the photocathode. Additional advantages could be increased polarization provided by the enhanced mobility of charge carriers that can be controlled by the SAW and the ionization of optically-generated excitons resulting in the creation of additional electron-hole pairs. It is expected that these novel features will reduce the cost of accelerator operation. A theoretical model for photoemission in the presence of SAW has been developed, and experimental tests of the technique are underway.