arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1105.0853quant-phcond-mat.stat-mechhep-th
收藏

簇-伊辛模型的统计力学

Statistical mechanics of the Cluster-Ising model

Pietro Smacchia, Luigi Amico, Paolo Facchi, Rosario Fazio, Giuseppe Florio, Saverio Pascazio, Vlatko Vedral

摘要:

研究了一个描述三自旋1/2团簇相互作用与类伊辛反铁磁相互作用竞争的哈密顿系统。我们计算了基态和热态的自由能、自旋关联函数和纠缠。该模型经历了一个量子相变之间的伊辛阶段与非零磁化和集群阶段的特点是由字符串顺序。任何双自旋纠缠被发现在两个量子相位消失,因为一个非平凡的相关模式。尽管如此,剩余的多体纠缠是最大的集群阶段,并依赖于在伊辛相的磁化。研究了临界点的块熵,计算了系统的中心荷,表明系统的临界性超出了Ising普适类.

英文摘要:

We study a Hamiltonian system describing a three-spin-1/2 cluster-like interaction competing with an Ising-like anti-ferromagnetic interaction. We compute free energy, spin correlation functions and entanglement both in the ground and in thermal states. The model undergoes a quantum phase transition between an Ising phase with a nonvanishing magnetization and a cluster phase characterized by a string order. Any two-spin entanglement is found to vanish in both quantum phases because of a nontrivial correlation pattern. Neverthless, the residual multipartite entanglement is maximal in the cluster phase and dependent on the magnetization in the Ising phase. We study the block entropy at the critical point and calculate the central charge of the system, showing that the criticality of the system is beyond the Ising universality class.

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。

↑