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arXiv:2505.15610 · Journal of Physics A Mathematical and Theoretical

Entanglement of inhomogeneous free bosons and orthogonal polynomials

Pierre-Antoine Bernard, Rafael I. Nepomechie, Gilles Parez, E. Ragoucy, David Raveh, Luc Vinet

Published Jul 16, 2025• 1 citation
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Abstract

Abstract In this paper, we investigate the ground-state entanglement entropy in inhomogeneous free-boson models in one spatial dimension. We develop a powerful method to extract the leading term in the entanglement scaling, based on the analytic properties of the inhomogeneous potential. This method is applicable to a broad class of models with smooth spatial inhomogeneities. As a case study, we apply this approach for a family of exactly-solvable models characterized by orthogonal polynomials of the Askey scheme, finding a perfect match between the numerical and analytical results.

DOI
10.1088/1751-8121/adf0b6

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