Entanglement entropy in quantum spin chains with broken parity number symmetry
نویسندگان
چکیده
Consider a generic quantum spin chain that can be mapped to free quadratic fermions via Jordan-Wigner (JW) transformation. In the presence of arbitrary boundary magnetic fields, this Hamiltonian is no longer after JW Using ancillary sites and enlarging we first introduce bigger Hamiltonian. Then diagonalize enlarged in its most form show all states are degenerate because zero mode. The eigenstates original with fields derived appropriate projection. We study in-depth properties particular, find: 1) configuration bases, 2) calculate correlation functions, 3) find reduced density matrices, 4) entanglement entropy. eigenstate (including chain) breaks parity number symmetry consequently one needs take care some technicalities regarding calculation matrix Interestingly structure these quite universal independent support our results by applying them couple examples.
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ژورنال
عنوان ژورنال: SciPost physics
سال: 2022
ISSN: ['2542-4653']
DOI: https://doi.org/10.21468/scipostphys.12.6.195