Articles dans des revues à comité de lecture
|Diverging conductance at the contact between random and pure quantum XX spin chains|
|J. Stat. Mech. (2017) 113301|
|DOI : 10.1088/1742-5468/aa933f|
|ArXiv : arxiv:1707.03192 [PDF]|
|HAL : hal-01559725|
A model consisting in 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 $\mu$ to the two baths. While a regime of linear characteristics $J$ versus $\Delta\mu$ 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.