Entanglement of inhomogeneous free fermions on hyperplane lattices

Autor: Bernard, Pierre-Antoine, Crampé, Nicolas, Nepomechie, Rafael I., Parez, Gilles, d'Andecy, Loïc Poulain, Vinet, Luc
Rok vydání: 2022
Předmět:
Zdroj: Nuclear Physics B 984 (2022) 115975
Druh dokumentu: Working Paper
DOI: 10.1016/j.nuclphysb.2022.115975
Popis: We introduce an inhomogeneous model of free fermions on a $(D-1)$-dimensional lattice with $D(D-1)/2$ continuous parameters that control the hopping strength between adjacent sites. We solve this model exactly, and find that the eigenfunctions are given by multidimensional generalizations of Krawtchouk polynomials. We construct a Heun operator that commutes with the chopped correlation matrix, and compute the entanglement entropy numerically for $D=2,3,4$, for a wide range of parameters. For $D=2$, we observe oscillations in the sub-leading contribution to the entanglement entropy, for which we conjecture an exact expression. For $D>2$, we find logarithmic violations of the area law for the entanglement entropy with nontrivial dependence on the parameters.
Comment: 27 pages, v3: corrected sign typo in Eq. (4.2)
Databáze: arXiv