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arXiv · 2209.01298

Steady off-diagonal long-range order state in a half-filled dimerized Hubbard chain induced by a resonant pulsed field

X. Z. Zhang·Z. Song
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Abstract

We show that a resonant pulsed field can induce a steady superconducting state even in the deep Mott insulating phase of the dimerized Hubbard model. The superconductivity found here in the non-equilibrium steady state is due to the $\eta $-pairing mechanism, characterized by the existence of the off-diagonal long-range order (ODLRO), and is absent in the ground-state phase diagram. The key of the scheme lies in the generation of the field-induced charge density wave (CDW) state that is from the valence bond solid. The dynamics of this state resides in the highly-excited subspace of dimerized Hubbard model and is dominated by a $\eta $-spin ferromagnetic model. The decay of such long-living excitation is suppressed because of energy conservation. We also develop a dynamical method to detect the ODLRO of the non-equilibrium steady state. Our finding demonstrates that the non-equilibrium many-body dynamics induced by the interplay between the resonant external field and electron-electron interaction is an alternative pathway to access a new exotic quantum state, and also provides an alternative mechanism for enhancing superconductivity.

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X. Z. Zhang, Z. Song. 2022-09-03. Steady off-diagonal long-range order state in a half-filled dimerized Hubbard chain induced by a resonant pulsed field. https://doi.org/10.1103/physrevb.106.094301

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