HIGHLY POLARIZED PHOTOLUMINESCENCE FROM 2-MU-M-THICK STRAINED GAAS GROWN ON CAF2

Citation
Lr. Tessler et al., HIGHLY POLARIZED PHOTOLUMINESCENCE FROM 2-MU-M-THICK STRAINED GAAS GROWN ON CAF2, Applied physics letters, 64(7), 1994, pp. 895-897
Citations number
18
Categorie Soggetti
Physics, Applied
Journal title
ISSN journal
00036951
Volume
64
Issue
7
Year of publication
1994
Pages
895 - 897
Database
ISI
SICI code
0003-6951(1994)64:7<895:HPPF2S>2.0.ZU;2-H
Abstract
Intense photoluminescence was measured in a strained 2-mu m-thick GaAs film grown on a (100)-oriented CaF2 substrate. Circular polarization of 77%+/-2% was obtained at 77 K under excitation with circularly pola rized photons below 1.575 eV. For excitation above 1.610 eV the polari zation is limited to 30%+/-2%. These results are clear indications of strain induced splitting between the M(j)=\+/-3/2> and the M(j)=\+/-1/ 2> hole bands. The deduced splitting was 62.5 +/- 2.5 meV, correspondi ng to a stress of the order of -12 kbar. The polarization is maximum f or reception energies very close to the excitation. Strained GaAs/CaF2 is thus a good candidate structure for efficient strongly polarized e lectron sources.