期刊论文详细信息
DIRECT OBSERVATION OF MINIBAND-EDGE SINGULARITIES IN THE OPTICAL-SPECTRA OF GAAS/ALAS SUPERLATTICES | |
Article | |
关键词: STARK LOCALIZATION; ELECTRIC-FIELD; DISPERSION; EXCITONS; STATES; | |
DOI : 10.1103/PhysRevB.49.1809 | |
来源: SCIE |
【 摘 要 】
Band-edge optical transitions in GaAs/AlAs superlattices with different miniband widths are investigated by low-temperature-photocurrent, photoluminescence-excitation, and reflectance spectroscopy. Direct spectroscopic evidence is given for excitonic effects at saddle-type critical points which are related to M(1) Van Hove singularities at the upper miniband edges, for both heavy-hole and light-hole excitons. Excellent agreement is obtained between the observed transition energies and the miniband widths deduced from Kronig-Penney model calculations.
【 授权许可】
Free