Diverging conductance at the contact between random and pure quantum XX spin chains. (10th November 2017)

• Record Type: Journal Article
• Authors: Christophe Chatelain,
• Is Part Of: Journal of statistical mechanics. (2017:Nov.)
• Publication Date: 2017-11-10
• Subjects: 2 -- 4; Statistical mechanics -- Periodicals; Mechanics -- Statistical methods -- Periodicals; 530.1305
• DOI: 10.1088/1742-5468/aa933f
• Languages: English
• ISSNs: 1742-5468

Abstract

Abstract: A model consisting of two quantum XX spin chains, one homogeneous and the second with random couplings drawn from a binary distribution, is considered. The two chains are coupled to two different non-local thermal baths and their dynamics is governed by a Lindblad equation. In the steady state, a current J is induced between the two chains by coupling them together by their edges and imposing different chemical potentials μ to the two baths. While a regime of linear characteristics J versus Δ μ is observed in the absence of randomness, a gap opens as the disorder strength is increased. In the infinite-randomness limit, this behavior is related to the density of states of the localized states contributing to the current. The conductance is shown to diverge in this limit.