论文标题
双层量子点接触的电导量化和射击噪声
Conductance quantization and shot noise of a double-layer quantum point contact
论文作者
论文摘要
第一个电导高原下方的电导量化和射击噪声$ g_0 = 2e^2/h $以GAAS/ALGAAS隧道耦合的双量子孔很好地测量量子点接触。从电导测量中，我们观察到一个清晰的量化电导高原为$ 0.5G_0 $，而跨导率最低为$ 0.7 g_0 $。光谱跨导量测量显示了第一个钻石内部的三个最大值，因此表明电源子带的分散关系中有三个最小值。射击噪声测量表明，Fano因子的行为与此观察结果一致。我们提出了一个模型，该模型将这些特征与波数定向分式子带相关联，这是由于强烈的rashba自旋 - 轨道相互作用，该相互作用是由双层样品的中心屏障电位梯度引起的。
The conductance quantization and shot noise below the first conductance plateau $G_0 = 2e^2/h$ are measured in a quantum point contact fabricated in a GaAs/AlGaAs tunnel-coupled double quantum well. From the conductance measurement, we observe a clear quantized conductance plateau at $0.5G_0$ and a small minimum in the transconductance at $0.7 G_0$. Spectroscopic transconductance measurement reveals three maxima inside the first diamond, thus suggesting three minima in the dispersion relation for electric subbands. Shot noise measurement shows that the Fano factor behavior is consistent with this observation. We propose a model that relates these features to a wavenumber directional split subband due to a strong Rashba spin--orbit interaction that is induced by the center barrier potential gradient of the double-layer sample.
