Entanglement, Ergodicity, and Many-Body Localization
APA
Abanin, D. (2014). Entanglement, Ergodicity, and Many-Body Localization. Perimeter Institute. https://pirsa.org/14050020
MLA
Abanin, Dmitry. Entanglement, Ergodicity, and Many-Body Localization. Perimeter Institute, May. 01, 2014, https://pirsa.org/14050020
BibTex
@misc{ pirsa_PIRSA:14050020, doi = {10.48660/14050020}, url = {https://pirsa.org/14050020}, author = {Abanin, Dmitry}, keywords = {}, language = {en}, title = {Entanglement, Ergodicity, and Many-Body Localization}, publisher = {Perimeter Institute}, year = {2014}, month = {may}, note = {PIRSA:14050020 see, \url{https://pirsa.org}} }
Talk Type
Abstract
We are used to describing systems of many particles by statistical mechanics. However, the basic postulate of statistical mechanics – ergodicity – breaks down in so-called many-body localized systems, where disorder prevents particle transport and thermalization. In this talk, I will present a theory of the many-body localized (MBL) phase, based on new insights from quantum entanglement. I will argue that, in contrast to ergodic systems, MBL eigenstates are not highly entangled. I will use this fact to show that MBL phase is characterized by an infinite number of emergent local conservation laws, in terms of which the Hamiltonian acquires a universal form. Turning to the experimental implications, I will describe the response of MBL systems to quenches: surprisingly, entanglement shows logarithmic in time growth, reminiscent of glasses, while local observables exhibit power-law approach to “equilibrium” values. I will support the presented theory with results of numerical experiments. I will close by discussing other directions in exploring ergodicity and its breaking in quantum many-body systems.