非厄米光子系统中的母哈密顿量与本征相变
Parent Hamiltonian and intrinsic phase transition in non-Hermitian photonic systems
AI总结：
本研究首次实验实现非厄米母哈密顿量，通过单光子验证其基态，观测到本征非厄米相变，为可控非厄米系统研究提供新途径。
AI中文摘要：
非厄米系统具有厄米物理学中不存在的现象，但实现具有本征非厄米性质的哈密顿量仍具挑战性。非厄米母哈密顿量（NH-PH）这一理论方法可从一对具有定制特性的矩阵积态（MPS）构建非厄米系统。本文首次实验生成了NH-PHs，该生成过程从代表不对称Affleck–Kennedy–Lieb–Tasaki（AKLT）态的MPS出发，通过生成的NH-PH的虚时演化，利用单光子验证其左右基态。随后通过测量四个不同序参量表征系统特性，这些序参量探测非互易关联、手性不平衡及常规反铁磁关联。此外，将该框架扩展至具有不同模型的更大系统时，观察到本征非厄米相变，表现为当指定零能模不再是全局最低能态时，序参量发生突变。本工作首次实验实现并表征了具有可控和可定制特性的非厄米哈密顿量，为探索不同物理平台上的本征非厄米现象开辟了新途径。
英文摘要：
Non-Hermitian systems host phenomena absent in Hermitian physics, but realizing Hamiltonians with intrinsic non-Hermitian properties remains challenging. The theoretical method of non-Hermitian parent Hamiltonian (NH-PH) enables the construction of a non-Hermitian system from a pair of matrix product states (MPSs) with tailored properties. Here, we report the first experimental generation of NH-PHs. This generation starts from MPSs that represent asymmetric Affleck--Kennedy--Lieb--Tasaki (AKLT) states. The construction is validated with single photons via imaginary-time evolution of the generated NH-PH to obtain its left and right ground states. We then characterize the properties of the system by measuring four different order parameters that probe non-reciprocal correlations, chiral imbalance, and conventional antiferromagnetic correlations. Furthermore, extending the framework to a larger system with a different model, we observe an intrinsic non-Hermitian phase transition, manifested by abrupt jumps of an order parameter when the designated zero-energy modes cease to be the globally lowest-energy states. Our work provides the first experimental realization and characterization of non-Hermitian Hamiltonians with controllable and customizable properties, opening new avenues for exploring intrinsic non-Hermitian phenomena across diverse physical platforms.
