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我们研究了７７Ｋ温度下掺杂弱耦合ＧａＡｓ／ＡｌＡｓ窄垒超晶格在流体静压力下的垂直输运，发现其输运性质与宽垒超晶格有很大不同．当在压力下ＡｌＡｓ垒层中的Ｘ基态子能级降至ＥΓ１子能级和ＥΓ２子能级中间或更低能量位置时，未观察到Γ－Γ共振隧穿到Γ－Ｘ共振隧穿的转变，Ｉ－Ｖ曲线上的平台并未随压力增大而收缩，反而稍有变宽．同时，平台电流随压力增大而增加，直到与ＥΓ１－ＥΓ１共振峰电流相当．我们认为，由于垒层很薄，Γ电子隧穿通过垒层的几率很高，ＥΓ１－ＥΓ１共振峰显著高于ＥΓ１－Ｅｘ１共振峰，因此，高场畴区内的输运机制在压力下仍由Γ－Γ级联共振隧穿控制．但由于Ｘ子能级随压力升高而降低，导致隧穿通过Γ－Ｘ垒的几率增加，非共振背景电流增大．由于电流连续性条件的要求，高场区的电场强度增强，导致在高压力下平台宽度随压力稍微变宽．
We studied the vertical transport of a weakly coupled GaAs / AlAs narrow-band superlattice at hydrostatic pressure at 77K and found that the transport properties are quite different from those of wide-barrier superlattices. No Γ-Γ resonant tunneling to Γ-X resonant tunneling was observed when the X-based state energy levels in the AlAs barrier under pressure dropped to intermediate or lower energy levels of the EΓ1 sub-level and the EΓ2 sub-level Change, I-V curve on the platform did not shrink with increasing pressure, but slightly widened. At the same time, the plateau current increases with increasing pressure until it is comparable to the EΓ1-EΓ1 formant current. We believe that the EΓ1-EΓ1 formant is significantly higher than the EΓ1-Ex1 formant due to the very thin barrier layer and the high probability of Γ electron tunneling through the barrier. Therefore, the transport mechanism in the high-field region remains under pressure By Γ-Γ cascade tunneling resonant control. However, as the X sub-level decreases with increasing pressure, the probability of tunneling through the Γ-X barrier increases and the non-resonant background current increases. Due to the requirements of current continuity conditions, the electric field strength in the high field region increases, resulting in the platform width slightly widening with pressure under high pressure.