arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2203.07784cond-mat.stat-mechcond-mat.quant-gas
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有耗散的团簇伊辛模型中的突现相变

Emergent phase transition in Cluster Ising model with dissipation

Zheng-Xin Guo, Xue-Jia Yu, Xi-Dan Hu, Zhi Li

摘要:

本文研究了一个具有非厄米外场的团簇伊辛模型,它可以用自由费米子的语言精确求解。通过考察能量密度的二阶导数和保真度,初步定位了可能的新临界点。然后检测串序参量和交错磁化,揭示全新特性的涌现相位。为了对由非厄米性引起的奇异相和相变进行分类,我们计算了自旋关联函数和弦参数的变化模式,它们表征了具有不同衰变模式和临界指数的涌现相和临界点.借助于弦序参量和交错磁化,我们发现在引入非厄米性后,存在四个相:团簇相、无隙相、顺磁相和反铁磁相。然后提出了一个相图,以图形方式说明,基于两个“KT类”相变和伊辛相变,分别为非厄米强度的增加,三个临界线的产生。我们的理论工作有望在超冷原子实验中得以实现,推动探索新相和相变的进展。

英文摘要:

We study a cluster Ising model with non-Hermitian external field which can be exactly solved in the language of free fermions. By investigating the second derivative of energy density and fidelity, the possible new critical points are tentatively located. String order parameter and staggered magnetization are then detected to reveal emergent phases of brand new characteristics. To categorize the exotic phases and phase transitions induced by non-Hermiticity, we calculate the variation mode of spin correlation function as well as string parameter, which characterize the emergent phases and critical points with different patterns of decay and critical exponents. With the help of string order parameter and staggered magnetization, we find that there are four phases after introducing the non-Hermiticity -- the cluster phase, the gapless phase, the paramagnetic (PM) phase and the antiferromagnetic (AF) phase. A phase diagram is then presented to graphically illustrate, based on two "KT-like" phase transitions and an Ising phase transition, respectively, the generation of three critical lines as non-Hermitian strength increases. Our theoretical work is expected to be realized in the experiment of ultra-cold atoms, pushing for progress in exploring novel phases and phase transitions.

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。

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