On Polynomial Lieb-Robinson Bounds for the XY Chain in a Decaying Random Field

Gebert, Martin; Lemm, Marius (2016): On Polynomial Lieb-Robinson Bounds for the XY Chain in a Decaying Random Field. In: Journal of Statistical Physics, Vol. 164, No. 3: pp. 667-679

Abstract

We consider the isotropic XY quantum spin chain in a random external field in the z direction, with single site distributions given by i.i.d. random variables times the critical decaying envelope . Our motivation is the study of many-body localization. We investigate transport properties in terms of polynomial Lieb-Robinson (PLR) bounds. We prove a zero-velocity PLR bound for large disorder strength and for small we show a partial converse, which suggests the existence of a transition to non-trivial transport in the model.

• Item Type: Journal article
• Faculties: Mathematics, Computer Science and Statistics > Mathematics
• Subjects: 500 Science > 510 Mathematics
• ISSN: 0022-4715
• Language: English