{ "id": "1508.07293", "version": "v1", "published": "2015-08-28T17:52:06.000Z", "updated": "2015-08-28T17:52:06.000Z", "title": "Spectral statistics across the many-body localization transition", "authors": [ "Maksym Serbyn", "Joel E. Moore" ], "comment": "5 pages, 3 figures", "categories": [ "cond-mat.dis-nn", "cond-mat.stat-mech", "quant-ph" ], "abstract": "The many-body localization transition (MBLT) between ergodic and many-body localized phase in disordered interacting systems is a subject of much recent interest. Statistics of eigenenergies is known to be a powerful probe of crossovers between ergodic and integrable systems in simpler examples of quantum chaos. We consider the evolution of the spectral statistics across the MBLT, starting with mapping to a Brownian motion process that analytically relates the spectral properties to the statistics of matrix elements. We demonstrate that the flow from Wigner-Dyson to Poisson statistics is a two-stage process. First, fractal enhancement of matrix elements upon approaching the MBLT from the metallic side produces an effective power-law interaction between energy levels, and leads to a plasma model for level statistics. At the second stage, the gas of eigenvalues has local interaction and level statistics belongs to a semi-Poisson universality class. We verify our findings numerically on the XXZ spin chain. We provide a microscopic understanding of the level statistics across the MBLT and discuss implications for the transition that are strong constraints on possible theories.", "revisions": [ { "version": "v1", "updated": "2015-08-28T17:52:06.000Z" } ], "analyses": { "keywords": [ "many-body localization transition", "spectral statistics", "matrix elements", "metallic side produces", "brownian motion process" ], "note": { "typesetting": "TeX", "pages": 5, "language": "en", "license": "arXiv", "status": "editable" } } }