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arXiv · 2307.05456

Many-Body Bound States in the Continuum

Shoki Sugimoto·Yuto Ashida·Masahito Ueda
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Abstract

A bound state in the continuum (BIC) is a spatially bounded energy eigenstate lying in a continuous spectrum of extended eigenstates. While various types of single-particle BICs have been found in the literature, whether or not BICs can exist in genuinely many-body systems remains inconclusive. Here, we provide numerical and analytical pieces of evidence for the existence of many-body BICs in a one-dimensional Bose-Hubbard chain with an attractive impurity potential, which was previously known to host a BIC in the two-particle sector. We also demonstrate that the many-body BICs prevent the system from thermalization when one starts from simple initial states that can be prepared experimentally.

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Shoki Sugimoto, Yuto Ashida, Masahito Ueda. 2023-07-11. Many-Body Bound States in the Continuum. https://arxiv.org/abs/2307.05456

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