Non-adiabatically driven electron in quantum wire with spin-orbit interaction

TL;DR

This paper presents an exact analytical solution for an electron in a quantum wire with spin-orbit interaction under a time-dependent harmonic potential, enabling precise spin control in non-adiabatic regimes.

Contribution

It introduces a formalism that allows exact solutions for spin dynamics and state occupations under non-adiabatic driving in quantum wires with spin-orbit coupling.

Findings

Perfect spin flips achievable at high frequencies.

Analytical expressions for spin and pseudo-spin rotations.

Implications for spin-polarized emission and transport.

Abstract

An exact solution is derived for the wave function of an electron in a semiconductor quantum wire with spin-orbit interaction and driven by external time dependent harmonic confining potential. The formalism allows analytical expressions for various quantities to be derived, such as spin and pseudo-spin rotations, energy and occupation probabilities for excited states. It is demonstrated how perfect spin and pseudo-spin flips can be achieved at high frequencies of order \omega, the confining potential level spacing. By an appropriately chosen driving term, spin manipulation can be exactly performed far into the non-adiabatic regime. Implications for spin-polarised emission and spin-dependent transport are also discussed.