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arXiv:cond-mat/0509338 · Physical Review B

Critical entanglement of XXZ Heisenberg chains with defects

Jize Zhao, Ingo Peschel, Xiaoqun Wang

Published Jan 24, 2006• 56 citations
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Abstract

We study the entanglement properties of anisotropic open spin one-half Heisenberg chains with a modified central bond. The entanglement entropy between the two half-chains is calculated with the density-matrix renormalization method (DMRG). We find a logarithmic behavior with an effective central charge ${c}^{\ensuremath{'}}$ varying with the length of the system. It flows to one in the ferromagnetic region and to zero in the antiferromagnetic region of the model. In the $XX$ case it has a nonuniversal limit and we recover previous results.

DOI
10.1103/physrevb.73.024417

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