Enhancement of Spin-Polarized Electron Emission from Strain-CompensatedAlInGaAs- GaAsP Superlattices
نویسنده
چکیده
Resonance enhancement of the quantum efficiency of new polarized electron photocathodes based on a short-period strain-compensated AlInGaAs/GaAsP superlattice structure is reported. The superlattice is a part of an integrated FabryPerot optical cavity. We demonstrate that the Fabry-Perot resonator enhances the quantum efficiency by up to a factor 10 in the wavelength region of the main polarization maximum. The high structural quality implied by these results points to the very promising application of these photocathodes for spin-polarized electron sources. Contributed to The 17 International Spin Physics Symposium (SPIN 2006)) October 2-7, 2006, Kyoto, Japan ∗ Work supported in part by U.S. Department of Energy under contract DE-AC02-76SF00515.
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