Ang Yee Sin, Ma Zhongshui, Zhang C
School of Physics, University of Wollongong, NSW 2522, Australia.
1] School of Physics, Peking University, Beijing 100871, China [2] Collaborative Innovation Center of Quantum Matter, Beijing, 100871, China.
Sci Rep. 2014 Jan 21;4:3780. doi: 10.1038/srep03780.
The unusual tunneling effects of massless chiral fermions (mCF) and massive chiral fermions (MCF) in a single layer graphene and bilayer graphene represent some of the most bizarre quantum transport phenomena in condensed matter system. Here we show that in a two-dimensional semiconductor with Rashba spin-orbit coupling (R2DEG), the real-spin chiral-like tunneling of electrons at normal incidence simultaneously exhibits features of mCF and MCF. The parabolic branch of opposite spin in R2DEG crosses at a Dirac-like point and has a band turning point. These features generate transport properties not found in usual two-dimensional electron gas. Albeit its π Berry phase, electron backscattering is present in R2DEG. An electron mimics mCF if its energy is in the vicinity of the subband crossing point or it mimics MCF if its energy is near the subband minima.
单层石墨烯和双层石墨烯中无质量手性费米子（mCF）和有质量手性费米子（MCF）的异常隧穿效应代表了凝聚态物质系统中一些最奇异的量子输运现象。在此我们表明，在具有Rashba自旋轨道耦合的二维半导体（R2DEG）中，电子在垂直入射时的实自旋类手性隧穿同时展现出mCF和MCF的特征。R2DEG中相反自旋的抛物线分支在一个类狄拉克点处交叉并且有一个能带转折点。这些特征产生了通常二维电子气中未发现的输运性质。尽管其具有π Berry相，但R2DEG中存在电子背散射。如果电子能量在子带交叉点附近，它模拟mCF；如果其能量在子带最小值附近，它模拟MCF。
