arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0904.1946quant-phcond-mat.str-el
收藏

磁场中一维海森堡量子自旋链的热纠缠

Thermal entanglement of one-dimensional Heisenberg quantum spin chains in magnetic fields

Shou-Shu Gong, Gang Su

摘要:

利用Jordan-Wigner变换精确求解了S = 1/2 XY链在横向磁场中的热成对纠缠。发现TE在一个与场无关的温度Tc~0.4843J处消失。提出了一个热量来证明纠缠态。利用转移矩阵重整化群方法研究了S = 1/2反铁磁-铁磁(AF-F)海森堡链的TE,发现AF和F相互作用耦合的自旋TE有明显的不同.观察到F相互作用耦合自旋的场致TE的消失温度随磁场的变化而变化。利用平均场论对所得结果进行了进一步的验证和分析。

英文摘要:

The thermal pairwise entanglement (TE) of the S=1/2 XY chain in a transverse magnetic field is exactly resolved by means of the Jordan-Wigner transformation. It is found that the TE vanishes at a common temperature Tc~0.4843J, which is irrelevant to the field. A thermal quantity is proposed to witness the entangled state. Furthermore, the TE of the S=1/2 antiferromagnetic-ferromagnetic (AF-F) Heisenberg chain is studied by the transfer-matrix renormalization group method.The TEs of the spins coupled by AF and F interactions are found to behave distinctively. The vanishing temperature of the field-induced TE of the spins coupled by F interactions is observed to change with the magnetic field. The results are further confirmed and analyzed by the mean-field theory.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑