Observation of many-body localization of interacting fermions in a quasi-random optical lattice

Michael Schreiber; Sean S. Hodgman; Pranjal Bordia; Henrik P. Lüschen; Mark H. Fischer; Ronen Vosk; Ehud Altman; Ulrich Schneider; Immanuel Bloch

doi:10.1126/science.aaa7432

arXiv · 1501.05661

Observation of many-body localization of interacting fermions in a quasi-random optical lattice

Michael Schreiber·Sean S. Hodgman·Pranjal Bordia·Henrik P. Lüschen·Mark H. Fischer·Ronen Vosk·Ehud Altman·Ulrich Schneider·Immanuel Bloch

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Abstract

We experimentally observe many-body localization of interacting fermions in a one-dimensional quasi-random optical lattice. We identify the many-body localization transition through the relaxation dynamics of an initially-prepared charge density wave. For sufficiently weak disorder the time evolution appears ergodic and thermalizing, erasing all remnants of the initial order. In contrast, above a critical disorder strength a significant portion of the initial ordering persists, thereby serving as an effective order parameter for localization. The stationary density wave order and the critical disorder value show a distinctive dependence on the interaction strength, in agreement with numerical simulations. We connect this dependence to the ubiquitous logarithmic growth of entanglement entropy characterizing the generic many-body localized phase.

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Michael Schreiber, Sean S. Hodgman, Pranjal Bordia, Henrik P. Lüschen, Mark H. Fischer, Ronen Vosk, Ehud Altman, Ulrich Schneider, Immanuel Bloch. 2015-01-22. Observation of many-body localization of interacting fermions in a quasi-random optical lattice. https://doi.org/10.1126/science.aaa7432

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