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利用高压光致发光方法在液氮温度下和０—３５ｋａｒ的压力范围内对不同层厚的ＧａＡｓ／Ａｌ０．３３Ｇａ０．６７Ａｓ短周期超晶格以及具有相近组份的Ａｌ０．３Ｇａ０．７Ａｓ体材料进行了系统的研究．测得Ａｌ０．３Ｇａ０．７Ａｓ体材料的Γ谷和Ｘ谷的压力系数分别为８．６ｍｅＶ／ｋｂａｒ和－．５７ｍｅＶ／ｋｂａｒ．在一定的压力范围内同时观测到了短周期超晶格中与类Γ态和类Ｘ态相关的发光峰，从而得到了类Γ态能级和类Ｘ态能级随压力的变化关系．首次获得了有关ＧａＡｓ／Ａｌ０．３３Ｇａ０．６７Ａｓ短周期超晶格能带不连续性（包括价带不连续性△Ｅｖ和导带不连续性△Ｅｃ）随压力变化的全部信息．实验结果表明这类短周期超晶格的△Ｅｖ和△Ｅｃ及其压力系数不仅与压力有关，而且与超晶格的周期有关．ｄ△Ｅｖ／ｄＰ和ｄ△Ｅｃ／ｄＰ随着周期的变短分别从（１０，１０）的０．２７ｍｅＶ／ｋｂａｒ和－２．４０ｍｅＶ／ｋｂａｒ增加和减小到（５，４）的４．０ｍｅｙ／ｋｂａｒ和－６．１ｍｅＶ／ｋｂａｒ．这种变化规律主要是由于超晶格中重空穴和Ｘ谷中电子束缚能△ｈｈ和△ｘ的压力系数ｄ△ｈｈ／ｄＰ和ｄ△ｘ／ｄＰ随着超晶格周期变短而迅速增加造成的．
High-pressure photoluminescence (PLG) method was used to fabricate GaAs / Al0.33Ga0.67As short-period superlattice and Al0.3Ga0.7As bulk materials with similar layer thicknesses at liquid nitrogen temperature and 0-35kar pressure range The systematic research. The measured pressure coefficients of the Γ and X valleys of the Al0.3Ga0.7As bulk material were 8.6 meV / kbar and -, respectively. 57meV / kbar. The luminescence peaks associated with the Γ-like and X-like states in the short-period superlattices were also observed within a certain pressure range. The relationship between the Γ-state energy levels and the X-like energy levels was obtained. For the first time, all the information on the band discontinuities of GaAs / Al0.33Ga0.67As short period superlattices (including △ Ve of conduction band discontinuity and ΔEc of conduction band discontinuities) was obtained. Experimental results show that △ Ev and △ Ec of these short-period superlattices and their pressure coefficients are not only related to pressure but also to the superlattice period. dΔEv / dP and dΔEc / dP increase and decrease from 0.27 meV / kbar and -2.40 meV / kbar of (10,10) to 4 of (5,4) respectively with decreasing period. 0 mey / kbar and -6.1 meV / kbar. The main reason for this change is that the pressure coefficients d △ hh / dP and d △ x / dP of the electron binding energy △ hh and △ x in the heavy cavities and the X valley in the superlattice rapidly increase as the superlattice period becomes shorter Caused.