The nonlinear Rashba effect in Hg_(077)Cd_(023)Te inversion layers probed by weak antilocalization analysis

摘要

The Rashba spin-orbit interaction of the two-dimensional electron gas with high mobility in the inversion layer of p-type Hg_(0.77)Cd_(0.23)Te is investigated by magnetotransport measurements. Both the Rashba spin splitting and Rashba coefficient are extracted by analysis of the weak anti-localization effect using the Golub model. It is found that both the splitting and coefficient increase with increasing electron density (～3.0-6.0 × 10~(15)m~(-2)), i.e., with the gate voltage. A self-consistent Schrodinger-Poisson calculation is performed and suggests that the nonlinear Rashba effect caused by the weakening of interband coupling, especially at high electron density, dominates this system.