Parent Hamiltonian and intrinsic phase transition in non-Hermitian photonic systems

@misc{xiao2026parent,
  title = {{Parent Hamiltonian and intrinsic phase transition in non-Hermitian photonic systems}},
  author = {Yuntao Xiao and Yuchen Guo and Xiaojian Huang and Huixia Gao and Dengke Qu and Lei Xiao and Kunkun Wang and Shuo Yang and Peng Xue},
  howpublished = {arXiv},
  year = {2026},
  month = jul,
  doi = {10.48550/arxiv.2607.28964},
  eprint = {2607.28964},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2607.28964},
}

TY  - UNPB
TI  - Parent Hamiltonian and intrinsic phase transition in non-Hermitian photonic systems
AU  - Yuntao Xiao
AU  - Yuchen Guo
AU  - Xiaojian Huang
AU  - Huixia Gao
AU  - Dengke Qu
AU  - Lei Xiao
AU  - Kunkun Wang
AU  - Shuo Yang
AU  - Peng Xue
PY  - 2026
DA  - 2026/07/31
PB  - arXiv
DO  - 10.48550/arxiv.2607.28964
UR  - https://arxiv.org/abs/2607.28964
AB  - 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.
ER  -