Measurement of Electron Beam Polarization from Unstrained Bulk GaAs via Two Photon Photoemission

Conference · Wed Jun 01 00:00:00 EDT 2011 · J. Phys.: Conf. Ser.

DOI:https://doi.org/10.1088/1742-6596/298/1/012018· OSTI ID:1021387

J L McCarter, T J Gay, J Hansknecht, M Poelker, M L Stutzman

This paper describes measurements of the beam polarization and quantum efficiency for photoemission using two-photon excitation from unstrained bulk GaAs illuminated with pulsed, high intensity 1560nm laser light. Quantum efficiency is linearly proportional to 1560nm peak laser intensity, which was varied in three independent ways, indicating that the emitted electrons are promoted from the valence to the conduction band via two-photon absorption. Beam polarization was measured using a microMott polarimeter, with a value of 16.8(4)% polarization at 1560nm, which is roughly half the measured value of 33.4(8)% using 778 nm light.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1021387
• Report Number(s): JLAB-ACC-10-1308; DOE/OR/23177-1665; TRN: US201116%%741
• Journal Information: J. Phys.: Conf. Ser., Vol. 298, Issue 01; Conference: PESP2010, 21–24, September 2010, Bonn, Germany
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ABSORPTION
BEAMS
DATA
ELECTRON BEAMS
ELECTRONS
EXCITATION
LASERS
PEAKS
PHOTOEMISSION
PHOTONS
POLARIZATION
QUANTUM EFFICIENCY
VALENCE
VISIBLE RADIATION