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arXiv · 1902.07947

Dynamically enhanced unconventional superconducting correlations in a Hubbard ladder

Ameneh Sheikhan·Corinna Kollath
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Abstract

We propose theoretically how unconventional superconducting pairing in a repulsively interacting Hubbard ladder can be enhanced via the application of a Floquet driving. Initially the Hubbard ladder is prepared in its charge-density-wave dominated ground state. A periodic Floquet drive is applied which modulates oppositely the energy offset of the two chains and effectively reduces the tunneling along the rungs. This modulation of the energy offsets might be caused by the excitation of a suitable phononic mode in solids or a superlattice modulation in cold atomic gases. We use state-of-the-art density matrix renormalization group methods to monitor the resulting real-time dynamics of the system. We find an enormous enhancement of the unconventional superconducting pair correlations by approximately one order of magnitude.

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Ameneh Sheikhan, Corinna Kollath. 2019-02-21. Dynamically enhanced unconventional superconducting correlations in a Hubbard ladder. https://doi.org/10.1103/physrevb.102.035163

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