摘要
在77K下测量了不同阱宽(30-160A)的In_xCa_(1-x)As/GaAs应变量子阱的静压下光致发光谱.静压范围为0-60kbar.发现导带第一子带到重空穴第一子带的激子发光峰的压力系数从 160A阱的 9.74meV/kbat增加到 30A 阱的 10.12meV/kbar.计算表明,阱变窄时电子波函数向压力系数较大的势垒层中的逐步扩展是压力系数随阱宽变小而增加的原因之一.在压力超过50kbar后观察到两个与间接跃迁有关的发光峰.
The photoluminescence of In_xGa_(1-x)As/GaAs strained quantum wells with the widths of30A to 160 A have been studied at 77 K under hydrostatic pressure up to 60 kbar. It is foundthat the pressure coefficients of exciton peaks from lst conduction subband to heavy hole sub-band increase from 9.74 meV/kbar of 160A well to 10.12 meV/kbar of 30 A well. The calcu-lation based on the Kronig-Penney model indicated that the extension of electronic wave fun-ction to barrier layer in the narrow wells is one of the reason for the increase of pressure-coefficients with the decrease of well width. Two peaks related to indirect transition were-observed at the pressure higher than 50 kbar.
