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arXiv · 1902.05012

Heating-Induced Long-Range $\eta$-Pairing in the Hubbard Model

Joseph Tindall·Berislav Buca·Jonathan R. Coulthard·Dieter Jaksch
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Abstract

We show how, upon heating the spin degrees of freedom of the Hubbard model to infinite temperature, the symmetries of the system allow the creation of steady-states with long-range correlations between $\eta$-pairs. With induce this heating with either dissipation or periodic driving and evolve the system towards a nonequilibrium steady state, a process which melts all spin order in the system. The steady state is identical in both cases and displays distance-invariant off-diagonal $\eta$-correlations. These correlations were first recognised in the superconducting eigenstates in Yang's seminal paper [Phys. Rev. Lett 63, 2144 (1989)], which are a subset of our steady states. We show that our results are a consequence of symmetry properties and entirely independent of the microscopic details of the model and the heating mechanism.

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Joseph Tindall, Berislav Buca, Jonathan R. Coulthard, Dieter Jaksch. 2019-02-13. Heating-Induced Long-Range $\eta$-Pairing in the Hubbard Model. https://doi.org/10.1103/physrevlett.123.030603

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