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arXiv · 1606.09122

Exact Bethe ansatz spectrum of a tight-binding chain with dephasing noise

Mariya V. Medvedyeva·Fabian H. L. Essler·Tomaz Prosen
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Abstract

We construct an exact map between a tight-binding model on any bipartite lattice in presence of dephasing noise and a Hubbard model with imaginary interaction strength. In one dimension, the exact many-body Liouvillian spectrum can be obtained by application of the Bethe ansatz method. We find that both the non-equilibrium steady state and the leading decay modes describing the relaxation at late times are related to the eta-pairing symmetry of the Hubbard model. We show that there is a remarkable relation between the time-evolution of an arbitrary k-point correlation function in the dissipative system and k-particle states of the corresponding Hubbard model.

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Mariya V. Medvedyeva, Fabian H. L. Essler, Tomaz Prosen. 2016-09-06. Exact Bethe ansatz spectrum of a tight-binding chain with dephasing noise. https://doi.org/10.1103/physrevlett.117.137202

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