arXiv:2003.02711 · Physics Letters B

Exact overlaps in the Lieb-Liniger model from coordinate Bethe ansatz

Hui-Huang Chen

Published Jul 20, 2020• 8 citations

Abstract

In the paper [1], the authors developed a new method to compute the exact overlap formulas between integrable boundary states and on-shell Bethe states in integrable spin chains. This method utilizes the coordinate Bethe ansatz representation of wave functions and singularity property of the off-shell overlaps. In this paper, we use this new method to derive the formula for overlaps between the Lieb-Liniger Bethe states and the Bose-Einstein condensate (BEC) state. As a simple application this method, we obtained the overlaps between the Lieb-Liniger eigenstates and the free particle states with pair structure.

DOI: 10.1016/j.physletb.2020.135631

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