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在室温和液氮温度下对不同层厚的GaAs/AlAs短周期超晶格在0—50kbar范围内进行了静压光致发光研究。在导带最低能级为类Γ态能级(Ⅰ类超晶格)和类X态能级(Ⅱ类超晶格)两种情况下都得到了类Γ态能级与类X态能级差随层厚的变化。首次直接观察到室温、常压下(GaAs)_(11)(AlAs)_(11)超晶格中类Γ态能级与类X态能级发生交叉。从发光峰的强度随压力的变化求得室温下在类Γ态能级与类X态能级恰好交叉的压力下类X态电子和类Γ态电子到价带空穴的跃迁几率之比从(GaAs)_(17)(AlAs)_(17)的1.4×10~(-4)逐渐增加到(GaAs)_6(AlAs)_6的4.6×10~(-3)。表明类Γ态和类X态间的混合较弱。对实验结果进行了简短的讨论。
The static pressure photoluminescence (PL) of GaAs / AlAs short-period superlattice with different layer thicknesses in the range of 0-50kbar was studied at room temperature and liquid nitrogen temperature. In the case of the lowest energy level of the conduction band, the Γ state energy level and the X state energy level difference are obtained under both the Γ state energy level (type I superlattices) and the X type energy level (type Ⅱ superlattices) With the layer thickness changes. It was observed for the first time that the Γ state energy level and the X-state energy level in the (GaAs) _ (11) (AlAs) _ (11) superlattice at room temperature and atmospheric pressure cross each other. The ratio of the transition probability of X-like electrons and the transition from the Γ-state electron to the valence band holes at room temperature under the pressure at which the Γ-state energy level and the X-state energy level just crosses from 1.4 × 10 -4 of (GaAs) _ (17) (AlAs) _ (17) gradually increased to 4.6 × 10 ~ (-3) of (GaAs) _6 (AlAs) _6. It shows that the mixture between Γ-state and X-like state is weaker. A brief discussion of the experimental results.