Excited state entanglement in homogeneous fermionic chains
Abstract
We study the Renyi entanglement entropy of an interval in a periodic fermionic chain for a general eigenstate of a free, translational invariant Hamiltonian. In order to analytically compute the entropy we use two technical tools. The first one is used to reduce logarithmically the complexity of the problem and the second one to compute the R\'enyi entropy of the chosen subsystem. We introduce new strategies to perform the computations, derive new expressions for the entropy of these general states and show the perfect agreement of the analytical computations and the numerical outcome. Finally we discuss the physical interpretation of our results and generalise them to compute the entanglement entropy for a fragment of a fermionic ladder.
Keywords
Cite
@article{arxiv.1401.5922,
title = {Excited state entanglement in homogeneous fermionic chains},
author = {F. Ares and J. G. Esteve and F. Falceto and E. Sánchez-Burillo},
journal= {arXiv preprint arXiv:1401.5922},
year = {2015}
}
Comments
31 pages, 1 table, 8 figures. Final version published in J. Phys. A. References and section added. Typos corrected