Coriolis force, geometric phase, and spin-electric coupling in semiconductors

TL;DR

This paper explores how electric fields induce a Coriolis-like force and geometric phases in semiconductors, leading to spin-electric coupling that affects charge carrier transport and spin dynamics without magnetic fields.

Contribution

It introduces a novel understanding of spin-electric coupling mediated by Coriolis forces and geometric phases, linking them to gauge potentials and controllable via external fields.

Findings

Effective spin-Hamiltonians similar to Rashba in conduction and light hole bands.

Spin-electric coupling can be controlled by gate fields or strain.

Gauge field strength relates to the electron g-tensor.

Abstract

We consider the response of an effective spin of a charge carrier to an adiabatic rotation of its crystal momentum induced by electric field. This rotation gives rise to Coriolis pseudo-force that is responsible for torque acting on the orbital momentum of a particle. Mediated by a spin-orbit coupling in the valence band this perturbation leads to a spin-electric coupling that may affect the coherent transport properties of a charge carrier and cause a spin precession in zero magnetic fields. In the static uniform electric field the derived effective spin-Hamiltonians of the carriers in the conduction and light hole bands are homologous to the Rashba Hamiltonian. These effects may be also interpreted as a manifestation of, in general, a non-Abelian gauge potential and can be described in purely geometric terms as a consequence of the corresponding holonomy. We demonstrate that in the conduction band the strength of the associated covariant gauge field is proportional to the effective electron g-tensor and is controllable by gate fields or a strain applied to the crystal.