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arXiv · 1803.02838

Beyond many-body localized states in a spin-disordered Hubbard model with pseudo-spin symmetry

Xiongjie Yu·Di Luo·Bryan K. Clark
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Abstract

A prime characterization of many-body localized (MBL) systems is the entanglement of their eigenstates; in contrast to the typical ergodic phase whose eigenstates are volume law, MBL eigenstates obey an area law. In this work, we show that a spin-disordered Hubbard model has both a large number of area-law eigenstates as well as a large number of eigenstates whose entanglement scales logarithmically with system size (log-law). This model, then, is a microscopic Hamiltonian which is neither ergodic nor many-body localized. We establish these results through a combination of analytic arguments based on the eta-pairing operators combined with a numerical analysis of eigenstates. In addition, we describe and simulate a dynamic time evolution approach starting from product states through which one can separately probe the area law and log-law eigenstates in this system.

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Xiongjie Yu, Di Luo, Bryan K. Clark. 2018-03-07. Beyond many-body localized states in a spin-disordered Hubbard model with pseudo-spin symmetry. https://doi.org/10.1103/physrevb.98.115106

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