Conservation laws and many-body localization

Conservation laws and many-body localization
Anushya Chandran, Perimeter Institute
Date and time: Mon, Dec 07, 2015 - 12:15pm
Refreshments at 12:00pm
Location: LGRT 1033
Category: Condensed Matter Seminar
Abstract:
Anderson localization is the remarkable quantum phenomenon of spatial localization of electrons in disordered media. It is traditionally diagnosed by the absence of charge and energy transport. Recent experiments in disordered cold atomic gases have brought into sharp focus the other striking aspects of localization: infinite persistence of local memory and the breakdown of statistical mechanics in highly excited states. In the last year, these and other experiments have begun to controllably explore the interacting regime and have raised many new questions about interacting localization or "many-body localization". In this talk, I will explore the role of conserved quantities in many-body localization (MBL). I will first show how a complete set of quasi-local conserved bits explains the properties of MBL. I will then argue that such a set arises in the MBL phase in one dimension and provide an explicit experimentally motivated construction of them in a disordered spin chain. In higher dimensions, the phenomenology has to be different; I will present a geometric setting of a MBL* phase with no local conserved quantities that nevertheless exhibits slow dynamics and has zero transport.