Aharonov Casher Phase Factor in Mesoscopic Interferometers

by Yshai Avishai

at Condensed Matter Theory Seminar

Wed, 24 Oct 2018, 13:30
Physics building (#54) room 207

Abstract

The Aharonov Casher phase factor is the SU 2 analog of the U 1 Aharonov Bohm phase factor exp i phi AB wherein phi AB the Aharonov Bohm phase is the line integral of the electromagnetic vector potential over a closed loop It plays an important role in mesoscopic systems in which spin orbit coupling is relevant but its experimental determination is rather elusive since unlike the occurrence of a simple relation between the magnetic flux through a loop and the U 1 Aharonov Bohm phase factor there is no similar SU 2 analog Based on the SU 2 gauge invariant formulation of the Schro dinger equation we relate the Aharonov Casher phase factor to measurable quantities in mesoscopic interferometers subject to electric fields that generate Rashba or Dresselhaus spin orbit coupling Specifically we consider electron transmission through 1 single channel ring interferometer and 2 a two channel square interferometer In both examples we derive a closed expression for the conductance and show that it is a simple rational function of the trace full part of the phase factor In the second case we derive a closed expression for the electron polarization vector and find it to be a simple function of both the trace full and traceless parts of the phase factor This analysis then suggests a direct way for an experimental measurement of the Aharonov Casher phase factor

Created on 16-10-2018 by Bar Lev, Yevgeny (ybarlev)
Updaded on 16-10-2018 by Bar Lev, Yevgeny (ybarlev)