Eur. Phys. J. B (2014) 87: 43
https://doi.org/10.1140/epjb/e2014-50042-4

Regular Article

Multiprobe quantum spin Hall bars

School of Physics, AMBER and CRANN, Trinity College, Dublin 2, Ireland

^a e-mail: narayaa@tcd.ie

Received: 28 November 2013
Received in final form: 18 January 2014
Published online: 19 February 2014

Abstract

We analyze electron transport in multiprobe quantum spin Hall (QSH) bars using the Büttiker formalism and draw parallels with their quantum Hall (QH) counterparts. We find that in a QSH bar the measured resistance changes upon introducing side voltage probes, in contrast to the QH case. We also study four- and six-terminal geometries and derive the expressions for the resistances. For these our analysis is generalized from the single-channel to the multi-channel case and to the inclusion of backscattering originating from a constriction placed within the bar.