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arXiv · 2111.12036

Quantum simulation of parity-time symmetry breaking with a superconducting quantum processor

Shruti Dogra·Artem A. Melnikov·Gheorghe Sorin Paraoanu
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Abstract

The observation of genuine quantum effects in systems governed by non-Hermitian Hamiltonians has been an outstanding challenge in the field. Here we simulate the evolution under such Hamiltonians in the quantum regime on a superconducting quantum processor by using a dilation procedure involving an ancillary qubit. We observe the parity-time ($\mathcal{PT}$)-symmetry breaking phase transition at the exceptional points, obtain the critical exponent, and show that this transition is associated with a loss of state distinguishability. In a two-qubit setting, we show that the entanglement can be modified by local operations.

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Shruti Dogra, Artem A. Melnikov, Gheorghe Sorin Paraoanu. 2021-11-23. Quantum simulation of parity-time symmetry breaking with a superconducting quantum processor. https://doi.org/10.1038/s42005-021-00534-2

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