The effects of boundary impurities on the entanglement entropy in an antiferromagnetic Heisenberg opened spin-1/2 chain are investigated. The method of density-matrix renormalization-group is used to obtain the bipartite entanglement. The entropy increases when the length of the subsystem increases. It will approach to a constant when system length is very large. With the same impurity interaction, qutrit impurities of spin-1 can increase the entanglement entropy.
@article{arxiv.1006.1732,
title = {Entanglement Entropy in an Antiferromagnetic Heisenberg Spin Chain with Boundary Impurities},
author = {Jie Ren and Shiqun Zhu and Xiang Hao},
journal= {arXiv preprint arXiv:1006.1732},
year = {2015}
}