Grundler D
Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung, Universität Hamburg, Jungiusstrasse 11, D-20355 Hamburg, Germany.
Phys Rev Lett. 2000 Jun 26;84(26 Pt 1):6074-7. doi: 10.1103/PhysRevLett.84.6074.
We report on zero-field spin splitting of two-dimensional electron systems. Though absent in the unbiased InAs square asymmetric quantum well (SAQW), the Rashba splitting becomes pronounced by applying a positive back-gate voltage. In our SAQW, the Rashba parameter alpha increases with electron density and is tuned by a factor of about 2 using an additional front gate without charging the well. We argue that the band-edge profile provides the important contribution for spin-orbit interaction due to barrier penetration of the envelope wave function. This mechanism can provide the potential for high speed implementation in spintronics.
我们报道了二维电子系统的零场自旋分裂。虽然在无偏置的砷化铟方形不对称量子阱（SAQW）中不存在，但通过施加正的背栅电压， Rashba 分裂变得明显。在我们的 SAQW 中，Rashba 参数α随电子密度增加，并且通过使用额外的前栅在不对量子阱充电的情况下可将其调节约 2 倍。我们认为，由于包络波函数的势垒穿透，能带边缘轮廓对自旋 - 轨道相互作用起重要作用。这种机制可为自旋电子学中的高速实现提供潜力。
