InxGa1-xAs-GaAs应变层量子阱结构的流体静压光荧光研究

本文报道了对分子束外延(MBE)生长的In_0.25Ga_0.75As-GaAs应变层量子阱结构在77K下的压力光荧光(PL)研究的结果。流体静压力从0到50kbar.,给出了In_0.25Ga_0.75As-GaAs应变层量子阱的Γ谷压力系数,实验观察到了量子阱中能级与势垒GaAs中X谷的能级交叉。通过对其压力行为的分析,给出了In_0.25Ga_0.75As-GaAs异质结的导带与价带跃变比:Q_c=△E_c:△E_v=0.68:0.32。对(InGa)As-GaAs应变量子阱常压下的理论分析与实验符合很好。本文也对Al_0.3Ga_0.70As-GaAs量子阱进行了讨论。 关键词：

PHOTOLUMINESCENCE STUDIES ON InxGa1-xAs-GaAs STRAINED QUANTUM WELLS STRUCTURE UNDER HYDROSTATIC PRESSURE

In this article we report the results of photoluminescence studies on In_0.25Ga_0.75 As-GaAs straiaed quantum wells grown by molecular beam epitaxy under pressure at 77 K. The applied hydrostatic pressure ranges from 0 to 50 kbar. The pressure coefficients of T valley of (InGa)As-GaAs strained quantum wells are presented. We have observed the crossover between the energy level in the well and X valley in the barrier GaAs. With the analysis of its behavior under pressure, the ratio of conduction band offset to valence band offset in In_0.25 Ga_0.75 As-GaAs heterojunction is determined as Q_c =△E_c:△E_v = 0.68:0.32. The theoretical studies on (InGa) AsGaAs strained quantum wells under normal pressure fit the experimental results very well. Some discussions about (AlGa)As-GaAs quantum wells are also included in this paper.