--- res: bibo_abstract: - We analyze a disordered central spin model, where a central spin interacts equally with each spin in a periodic one-dimensional (1D) random-field Heisenberg chain. If the Heisenberg chain is initially in the many-body localized (MBL) phase, we find that the coupling to the central spin suffices to delocalize the chain for a substantial range of coupling strengths. We calculate the phase diagram of the model and identify the phase boundary between the MBL and ergodic phase. Within the localized phase, the central spin significantly enhances the rate of the logarithmic entanglement growth and its saturation value. We attribute the increase in entanglement entropy to a nonextensive enhancement of magnetization fluctuations induced by the central spin. Finally, we demonstrate that correlation functions of the central spin can be utilized to distinguish between MBL and ergodic phases of the 1D chain. Hence, we propose the use of a central spin as a possible experimental probe to identify the MBL phase.@eng bibo_authorlist: - foaf_Person: foaf_givenName: Daniel foaf_name: Hetterich, Daniel foaf_surname: Hetterich - foaf_Person: foaf_givenName: Norman foaf_name: Yao, Norman foaf_surname: Yao - foaf_Person: foaf_givenName: Maksym foaf_name: Serbyn, Maksym foaf_surname: Serbyn foaf_workInfoHomepage: http://www.librecat.org/personId=47809E7E-F248-11E8-B48F-1D18A9856A87 orcid: 0000-0002-2399-5827 - foaf_Person: foaf_givenName: Frank foaf_name: Pollmann, Frank foaf_surname: Pollmann - foaf_Person: foaf_givenName: Björn foaf_name: Trauzettel, Björn foaf_surname: Trauzettel bibo_doi: 10.1103/PhysRevB.98.161122 bibo_issue: '16' bibo_volume: 98 dct_date: 2018^xs_gYear dct_identifier: - UT:000448596500002 dct_language: eng dct_publisher: American Physical Society@ dct_title: Detection and characterization of many-body localization in central spin models@ ...