Enhanced Rashba effect for hole states in a quantum dot

TL;DR

This paper investigates how Rashba spin-orbit interaction significantly influences hole states in quantum dots, revealing a larger spin-orbit gap compared to electrons, with implications for spin-dependent tunneling.

Contribution

It demonstrates an enhanced Rashba effect on hole states in quantum dots and analyzes its impact on the energy spectrum and potential tunneling applications.

Findings

Rashba SO coupling causes level repulsions among hole states.

The spin-orbit gap for holes is larger than for electrons.

Inter-hole interactions only slightly reduce the spin-orbit gap.

Abstract

The effect of Rashba spin-orbit (SO) interaction on the hole states in a quantum dot is studied in the presence of an external magnetic field. We demonstrate here that the Rashba SO coupling has a profound effect on the energy spectrum of the holes revealing level repulsions between the states with the same total momentum. We also show that the resulting spin-orbit gap is much larger than the corresponding one for the electron energy levels in a quantum dot. Inter-hole interactions only marginally reduce the spin-orbit gap. This enhanced Rashba effect would manifest itself in the tuneling current which depends on the spin-orbit coupling strength.