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arXiv · 2605.13008

Quantum dynamics of two $XX$ interacting PT-symmetric non-Hermitian qubits: enhancement of quantum annealing

Yana Komissarova·Mikhail V. Fistul·Ilya M. Eremin
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Abstract

Quantum information platforms enable analog quantum simulations, such as quantum annealing, offering a promising route to solving complex combinatorial optimization problems. Here, we propose a quantum information architecture based on networks of interacting parity-time (PT)-symmetric non-Hermitian qubits. While the dynamics of individual PT-symmetric qubits have been experimentally demonstrated across multiple platforms including NV centers, superconducting circuits, and trapped-ion systems yet coherent dynamics in interacting systems remain largely unexplored. To address this issue we theoretically investigate stationary and time-dependent Hamiltonians relevant to quantum annealing using a minimal model of two interacting XX-coupled PT-symmetric non-Hermitian qubits. We analyze both symmetry-preserving and symmetry-broken regimes and demonstrate that adding even tiny PT-symmetric non-Hermitian terms in the qubits Hamiltonian allows to greatly enhance the probability of reaching the ground state after annealing.

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Yana Komissarova, Mikhail V. Fistul, Ilya M. Eremin. 2026-05-13. Quantum dynamics of two $XX$ interacting PT-symmetric non-Hermitian qubits: enhancement of quantum annealing. https://arxiv.org/abs/2605.13008

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