当前位置: X-MOL 学术Phys. Rev. B › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Probing phase transitions in non-Hermitian systems with multiple quantum coherences
Physical Review B ( IF 3.2 ) Pub Date : 2021-10-25 , DOI: 10.1103/physrevb.104.155141
Diego Paiva Pires 1 , Tommaso Macrì 2, 3
Affiliation  

Understanding the interplay between quantum coherence and non-Hermitian features would enable the devising of quantum technologies based on dissipative systems. In turn, quantum coherence can be characterized in terms of the language of multiple quantum coherences (MQCs) originally developed in solid-state nuclear magnetic resonance (NMR), nowadays applied to the detection of quantum chaos and to the study of criticality in many-body quantum systems. Here, we show the usefulness of MQCs for probing equilibrium phase transitions in non-Hermitian systems. To do so, we investigate the connection of quantum coherences and critical points for several paradigmatic non-Hermitian Hamiltonians. For a non-Hermitian two-level system, MQCs witness the parity-symmetry-breaking phase transition from the unbroken to the broken phase. Furthermore, for the non-Hermitian transverse field Ising model, MQCs capture the Yang-Lee phase transition in which the ground state energy acquires a nonzero imaginary component. For the disordered Hatano-Nelson (HN) model with periodic boundary conditions, MQCs testify the emergence of mobility edges in the spectrum of this model. In addition, MQCs signal the topological phase transition exhibited by the complex energy spectra of the disorder-free HN model. Finally, we comment on experimentally probing phase transitions in NMR systems, realizing non-Hermitian Hamiltonians. Our results have applications to non-Hermitian quantum sensing, quantum thermodynamics, and in the study of the non-Hermitian skin effect.

中文翻译:

探索具有多重量子相干性的非厄米系统中的相变

了解量子相干性和非厄米特征之间的相互作用将有助于设计基于耗散系统的量子技术。反过来,量子相干性可以用最初在固态核磁共振 (NMR) 中开发的多重量子相干性 (MQC) 的语言来表征,现在应用于量子混沌的检测和许多关键性的研究——体量子系统。在这里,我们展示了 MQC 在探测非厄米系统中的平衡相变方面的有用性。为此,我们研究了几个范式非厄米哈密顿量的量子相干性和临界点的联系。对于非厄米两能级系统,MQC 见证了从未破相到破相的奇偶对称破缺相变。此外,对于非厄米横向场 Ising 模型,MQC 捕获 Yang-Lee 相变,其中基态能量获得非零虚部。对于具有周期性边界条件的无序 Hatano-Nelson (HN) 模型,MQC 证明在该模型的频谱中出现了迁移率边缘。此外,MQC 表示无序 HN 模型的复杂能谱所表现出的拓扑相变。最后,我们评论了实验探测 NMR 系统中的相变,实现非厄米哈密顿量。我们的结果可应用于非厄米量子传感、量子热力学以及非厄米趋肤效应的研究。对于具有周期性边界条件的无序 Hatano-Nelson (HN) 模型,MQC 证明在该模型的频谱中出现了迁移率边缘。此外,MQC 表示无序 HN 模型的复杂能谱所表现出的拓扑相变。最后,我们评论了实验探测 NMR 系统中的相变,实现非厄米哈密顿量。我们的结果可应用于非厄米量子传感、量子热力学以及非厄米趋肤效应的研究。对于具有周期性边界条件的无序 Hatano-Nelson (HN) 模型,MQC 证明在该模型的频谱中出现了迁移率边缘。此外,MQC 表示无序 HN 模型的复杂能谱所表现出的拓扑相变。最后,我们评论了实验探测 NMR 系统中的相变,实现非厄米哈密顿量。我们的结果可应用于非厄米量子传感、量子热力学以及非厄米趋肤效应的研究。我们评论了 NMR 系统中的实验探测相变,实现了非厄米哈密顿量。我们的结果可应用于非厄米量子传感、量子热力学以及非厄米趋肤效应的研究。我们评论了 NMR 系统中的实验探测相变,实现了非厄米哈密顿量。我们的结果可应用于非厄米量子传感、量子热力学以及非厄米趋肤效应的研究。
更新日期:2021-10-26
down
wechat
bug