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arXiv · 1912.07080

Non-equilibrium $d-$ wave pair density wave order parameter in superconducting cuprates

Mikhail Malakhov·Maxim Avdeev
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Abstract

We investigate the nonequilibrium pair density wave order parameter in a simple microscopic model with the ground state $d-$ wave spatially uniform superconductivity. After pushing the system out of equilibrium by a short-time induced order parameter, the system can exhibit robust free nondecaying oscillations of nonuniform superconducting order. In the weak nonequilibrium regime, the frequency of these oscillations is about $2\Delta/\hbar$ and the amplitude can be explained qualitatively by features of equilibrium free energy. In case when the system was taken far from equilibrium, it transits to a non-linear regime where even metastable coexistence of $d-$ wave superconducting and pair density wave gaps are possible.

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Mikhail Malakhov, Maxim Avdeev. 2019-12-15. Non-equilibrium $d-$ wave pair density wave order parameter in superconducting cuprates. https://arxiv.org/abs/1912.07080

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