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arXiv · 1807.05969

Frustration induced quasi-many-body localization without disorder

Sayan Choudhury·Eun-ah Kim·Qi Zhou
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Abstract

Motivated by the question of whether disorder is a prerequisite for localization to occur in quantum many-body systems, we study a frustrated one-dimensional spin chain, which supports localized many-body eigenstates in the absence of disorder. When the system is prepared in an initial state with one domain wall, it exhibits characteristic signatures of quasi-many-body localization (quasi- MBL), including initial state memory retention, an exponentially increasing lifetime with enlarging the size of the system, a logarithmic growth of entanglement entropy, and a logarithmic light cone of an out-of-time-ordered correlator. We further show that the localized many-body eigenstates can be manipulated as pseudospin-1/2s and thus could potentially serve as qubits. Our findings suggest a new route of using frustration to access quasi-MBL and preserve quantum coherence.

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Sayan Choudhury, Eun-ah Kim, Qi Zhou. 2018-07-16. Frustration induced quasi-many-body localization without disorder. https://arxiv.org/abs/1807.05969

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