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  • Open Access

Quantum simulation of two-level PT-symmetric systems using Hermitian Hamiltonians

Maryam Abbasi1, Koray Aydoğan2, Anthony W. Schlimgen1, and Kade Head-Marsden1,2,*

  • *Contact author: khm@umn.edu
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Phys. Rev. Research 8, 013034 – Published 14 January, 2026

DOI: https://doi.org/10.1103/gwbz-mbfw

Abstract

Parity-time (PT)-symmetric Hamiltonians exhibit nonunitary dynamical evolution while maintaining real spectra, and offer unique approaches to quantum sensing and entanglement generation. Here, we present a method for simulating the quantum dynamics of PT-symmetric systems on unitary-gate-based quantum computers by leveraging Hermitian equivalents through similarity transformations. We introduce two algorithms for simulating PT-symmetric systems near exceptional points where eigenvalues and eigenstates coalesce. The first is a hybrid classical-quantum algorithm and the second reduces the classical component by using an ancilla qubit. We then use perturbation theory to extend this method to consider the dynamics of two weakly interacting PT-symmetric systems. Demonstrations on a quantum device and noisy simulators validate the algorithm on current quantum devices, offering potential for scalable simulations of PT-symmetric systems and pseudo-Hermitian operators in quantum computation.

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Phys. Rev. Research 8, 013034– Published 14 January, 2026
  • Received 24 March 2025
  • Accepted 30 December 2025
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