Direct observation of spin-orbit splitting and phonon-assisted optical transitions in the valence band by internal photoemission spectroscopy

Article

关键词: P-TYPE GERMANIUM;    GALLIUM-ARSENIDE;    TEMPERATURE-DEPENDENCE;    INFRARED-SPECTROSCOPY;    CRITICAL-POINTS;    GAAS;    ABSORPTION;    SEMICONDUCTORS;    ENERGY;    INTERFACE;   

DOI  :  10.1103/PhysRevB.88.201302

来源: SCIE

【 摘 要 】

We employ internal photoemission spectroscopy to directly measure the valence-band Van Hove singularity, and identify phonons participating in indirect intervalence-band optical transitions. Photoemission of holes photoexcited through transitions between valence bands displays a clear and resolvable threshold, unlike previous reports of interband critical points which become obscure in doped materials. We also demonstrate the enhancement of optical phonon-assisted features primarily contributing to the photoemission yield. This result is evidence of the relaxation of photoexcited hot holes through intravalence-band scatterings in heterojunctions, which contrast with intervalence-band scatterings in bulks.

【 授权许可】

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