摘要
GaSb（Bi）/Alo.2Gao.sSb single quantum wells are characterized by a Fourier transform infrared spectrometer- based photoreflectance method at 77K. Spatially direct and indirect transitions between the electronic levels at and above the effective band gap are well resolved. The shifts of the electronic levels with Bi incorporation are identified quantitatively. The results show that the upshift of the valence band edge is clarified to be dominant, while the Bi-induced downshift of the conduction band edge does exist and contributes to the band gap reduction in the GaSbBi quantum-well layer by （29±6）%.
GaSb（Bi）/Alo.2Gao.sSb single quantum wells are characterized by a Fourier transform infrared spectrometer- based photoreflectance method at 77K. Spatially direct and indirect transitions between the electronic levels at and above the effective band gap are well resolved. The shifts of the electronic levels with Bi incorporation are identified quantitatively. The results show that the upshift of the valence band edge is clarified to be dominant, while the Bi-induced downshift of the conduction band edge does exist and contributes to the band gap reduction in the GaSbBi quantum-well layer by （29±6）%.
基金
Supported by the National Basic Research Program of China under Grant No 2014CB643901
the National Natural Science Foundation of China under Grant Nos 11274329 and 61321492
the Key Research Program of the Chinese Academy of Sciences under Grant Nos XDA5-1 and KGZD-EW-804
