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本文报道弹性应变及结构参数对 InAs/GaAs应变层超晶格导带、价带不连续性及其子能带结构的影响.通过分析流体静应力和单轴应力对体材料带边能带位置的影响,确定了 InAs/GaAs超晶格导带及价带能量不连续性,并用包络函数法计算了该超晶格的子能带结构.结果表明:这些量不仅依赖于组成超晶格的两种材料的体性质,而且还依赖于超晶格的晶格常数,势阱、势垒宽度以及材料的应变;通过调节InAs层与 GaAs层的层厚之比,可以使 InAs/GaAs超晶格价带轻空穴处于第Ⅱ类超晶格势当中,从而实现轻空穴与电子、重空穴的空间分离.
In this paper, the influence of elastic strain and structure parameters on the conduction band, valence band discontinuity and sub-band structure of InAs / GaAs strained layers are reported.Based on the analysis of fluid static stress and uniaxial stress, And the energy band discontinuities of InAs / GaAs superlattice were determined. The subband structure of the superlattice was calculated by the envelope function method. The results show that these quantities depend not only on the composition of the superlattice But also depends on the lattice constant, potential well, potential barrier width and material strain of the superlattice; by adjusting the ratio of the thickness of the InAs layer and the GaAs layer, the InAs / GaAs super The lattice valence band with light holes is in the class Ⅱ superlattice potential, so as to realize the spatial separation of light holes and electrons and heavy holes.