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arXiv · 1711.00828

Noisy Spins and the Richardson-Gaudin Model

Daniel A. Rowlands·Austen Lamacraft
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Abstract

We study a system of spins (qubits) coupled to a common noisy environment, each precessing at its own frequency. The correlated noise experienced by the spins implies long-lived correlations that relax only due to the differing frequencies. We use a mapping to a non-Hermitian integrable Richardson-Gaudin model to find the exact spectrum of the quantum master equation in the high-temperature limit, and hence determine the decay rate. Our solution can be used to evaluate the effect of inhomogeneous splittings on a system of qubits coupled to a common bath.

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Daniel A. Rowlands, Austen Lamacraft. 2017-11-02. Noisy Spins and the Richardson-Gaudin Model. https://doi.org/10.1103/physrevlett.120.090401

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