Experimental demonstration of the time reversal Aharonov-Casher effect

TL;DR

This paper experimentally demonstrates the time reversal Aharonov-Casher effect in mesoscopic semiconductor rings, showing control over spin precession via electrostatic gating and mapping the phase to spin-orbit interaction parameters.

Contribution

It provides the first experimental observation of the time reversal AC effect in mesoscopic rings with tunable spin precession control.

Findings

Controlled spin precession rate with electrostatic gates

Observation of second harmonic oscillations in AC interference

Mapping of AC phase to spin-orbit interaction parameter alpha

Abstract

We demonstrate the time reversal Aharonov-Casher (AC) effect in small arrays of mesoscopic semiconductor rings. By using an electrostatic gate we can control the spin precession rate and follow the AC phase over several interference periods. We show that we control the precession rate in two different gate voltage ranges; in the lower range the gate voltage dependence is strong and linear and in the higher range the dependence in almost an order of magnitude weaker. We also see the second harmonic of the AC interference, oscillating with half the period. We finally map the AC phase to the spin-orbit interaction parameter alpha and find it is consistent with Shubnikov-de Haas analysis.