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arXiv · 2301.12448

Construction of Non-Hermitian Parent Hamiltonian from Matrix Product States

Ruohan Shen·Yuchen Guo·Shuo Yang
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Abstract

There are various research strategies used for non-Hermitian systems, which typically involve introducing non-Hermitian terms to pre-existing Hermitian Hamiltonians. It can be challenging to directly design non-Hermitian many-body models that exhibit unique features not found in Hermitian systems. In this Letter, we propose a new method to construct non-Hermitian many-body systems by generalizing the parent Hamiltonian method into non-Hermitian regimes. This allows us to build a local Hamiltonian using given matrix product states as its left and right ground states. We demonstrate this method by constructing a non-Hermitian spin-$1$ model from the asymmetric Affleck-Kennedy-Lieb-Tasaki (AKLT) state, which preserves both chiral order and symmetry-protected topological order. Our approach opens up a new paradigm for systematically constructing and studying non-Hermitian many-body systems, providing guiding principles to explore new properties and phenomena in non-Hermitian physics.

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Ruohan Shen, Yuchen Guo, Shuo Yang. 2023-01-29. Construction of Non-Hermitian Parent Hamiltonian from Matrix Product States. https://doi.org/10.1103/physrevlett.130.220401

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