Abstract:
Degeneracy and symmetry have a profound relation in quantum systems. Here, we report gate-tunable subband degeneracy in PbTe nanowires with a nearly symmetric cross-sectional shape. The degeneracy is revealed in electron transport by the absence of a quantized plateau. Utilizing a dual gate design, we can apply an electric field to lift the degeneracy, reflected as emergence of the plateau. This degeneracy and its tunable lifting were challenging to observe in previous nanowire experiments, possibly due to disorder. Numerical simulations can qualitatively capture our observation, shedding light on device parameters for future applications.
摘要:
简并性和对称性在量子系统中有着深远的关系。这里,我们报道了具有几乎对称横截面形状的PbTe纳米线中的门可调谐子带简并性。由于没有量子化平台,在电子传输中揭示了简并性。利用双门设计,我们可以施加电场来提升简并性,反映为高原的出现。在先前的纳米线实验中观察到这种简并性及其可调提升是具有挑战性的,可能是由于混乱。数值模拟可以定性地捕获我们的观察结果,为未来的应用提供器件参数的光照。