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arXiv · 2607.01364

Decohered toric code under quantum damping noise and its mapping to a classical spin model

Nihar Ranjan Dash·Sanjoy Dutta·R. Srikanth·Subhashish Banerjee
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Abstract

We investigate properties of toric codes under realistic damping error channels, which include squeezing, thermal and non-Markovian effects. First, we map the decohered toric code under the generalized amplitude-damping (GAD) and the squeezed generalized amplitude-damping (SGAD) channels to the statistical-mechanical models using the double Hilbert-space formalism. Second, we map the action of the GAD and SGAD channels on the toric code to stochastic Pauli-type errors via Pauli twirling, yielding asymmetric depolarizing channels, and obtain the logical failure probabilities as a function of temperature and squeezing. In both cases, we relate the channel parameters of the GAD and SGAD channels to the spin-coupling constants of the statistical-mechanical model.

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Nihar Ranjan Dash, Sanjoy Dutta, R. Srikanth, Subhashish Banerjee. 2026-07-01. Decohered toric code under quantum damping noise and its mapping to a classical spin model. https://arxiv.org/abs/2607.01364

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