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arXiv · 1806.02571

Accessing eigenstate spin-glass order from reduced density matrices

Younes Javanmard·Soumya Bera·Markus Heyl
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Abstract

Many-body localized phases may not only be characterized by their ergodicity breaking, but can also host ordered phases such as the many-body localized spin-glass (MBL-SG). The MBL-SG is challenging to access in a dynamical measurement and therefore experimentally since the conventionally used Edwards-Anderson order parameter is a two-point correlation function in time. In this work, we show that many-body localized spin-glass order can also be detected from two-site reduced density matrices, which we use to construct an eigenstate spin-glass order parameter. We find that this eigenstate spin-glass order parameter captures spin-glass phases in random Ising chains both in many-body eigenstates as well as in the nonequilibrium dynamics from a local in time measurement. We discuss how our results can be used to observe MBL-SG order within current experiments in Rydberg atoms and trapped ion systems.

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Younes Javanmard, Soumya Bera, Markus Heyl. 2018-06-07. Accessing eigenstate spin-glass order from reduced density matrices. https://doi.org/10.1103/physrevb.99.144201

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