Entanglement in XY Spin Chain
量子物理
2009-11-10 v4 统计力学
可精确求解与可积系统
摘要
We consider the ground state of the XY model on an infinite chain at zero temperature. Following Bennett, Bernstein, Popescu, and Schumacher we use entropy of a sub-system as a measure of entanglement. Vidal, Latorre, Rico and Kitaev conjectured that von Neumann entropy of a large block of neighboring spins approaches a constant as the size of the block increases. We evaluated this limiting entropy as a function of anisotropy and transverse magnetic field. We used the methods based on integrable Fredholm operators and Riemann-Hilbert problem. The entropy is singular at phase transitions.
引用
@article{arxiv.quant-ph/0409027,
title = {Entanglement in XY Spin Chain},
author = {A. R. Its and B. -Q. Jin and V. E. Korepin},
journal= {arXiv preprint arXiv:quant-ph/0409027},
year = {2009}
}
备注
8 pages and 2 figures