Conductance quantization in PbTe nanowires
Wenyu Song, Yuhao Wang, Wentao Miao, Zehao Yu, Yichun Gao, Ruidong Li, Shuai Yang, Fangting Chen, Zuhan Geng, Zitong Zhang, Shan Zhang, Yunyi Zang, Zhan Cao, Dong E. Liu, Runan Shang, Xiao Feng, Lin Li, Qi-Kun Xue, Ke He, Hao Zhang
Abstract
PbTe nanowires coupled to a superconductor have recently been proposed as a potential Majorana platform. The hallmark of the one-dimensional nature of ballistic nanowires is their quantized conductance. Here, we report the observation of conductance plateaus at multiples of the quantized value $2{e}^{2}/h$ in PbTe nanowires at finite magnetic fields. The quantized plateaus, as a function of source-drain bias and magnetic field, allow for the extraction of the Land\'e $g$ factor, sub-band spacing, and effective mass. The coefficient of 2 in the plateau conductance indicates the presence of valley degeneracy arising from the crystal orientation of the nanowires, which are grown on a (001) substrate. Occasionally, this degeneracy can be lifted by a gate voltage that breaks the mirror symmetry. Our results demonstrate the one dimensionality of PbTe nanowires and fulfill one of the necessary conditions for the realization of Majorana zero modes.