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arXiv · 2412.13674

Manifolds of exceptional points and effective Zeno limit of an open two-qubit system

Vladislav Popkov·Carlo Presilla·Mario Salerno
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Abstract

We analytically investigate the Liouvillian exceptional point manifolds (LEPMs) of a two-qubit open system, where one qubit is coupled to a dissipative polarization bath. Exploiting a Z_2 symmetry, we block-diagonalize the Liouvillian and show that one symmetry block yields two planar LEPMs while the other one exhibits a more intricate, multi-sheet topology. The intersection curves of these manifolds provide a phase diagram for effective Zeno transitions at small dissipation. These results are consistent with a perturbative extrapolation from the strong Zeno regime. Interestingly, we find that the fastest relaxation to the non-equilibrium steady state occurs on LEPMs associated with the transition to the effective Zeno regime.

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Vladislav Popkov, Carlo Presilla, Mario Salerno. 2024-12-18. Manifolds of exceptional points and effective Zeno limit of an open two-qubit system. https://arxiv.org/abs/2412.13674

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