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arXiv · 2206.07752

Enigma of the vortex state in a strongly correlated d-wave superconductor

Abstract

We show that strong electronic repulsion transforms a vortex core from a metallic-type in overdoped regime to a Mott-insulator at underdoping of a strongly correlated d-wave superconductor. This changeover is accompanied by an accumulation of electron density at the vortex core towards local half-filling in the underdoped region, which in turn facilitates the formation of the Mott insulating core. We find that the size of vortices evolves non-monotonically with doping. A similar non-monotonicity of critical field $H_{\rm c2}$, as extracted from superfluid stiffness, is also found. Our results explain some recent experimental puzzles of cuprate superconductors.

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Anushree Datta, Hitesh J. Changlani, Kun Yang, Amit Ghosal. 2022-06-15. Enigma of the vortex state in a strongly correlated d-wave superconductor. https://doi.org/10.1103/physrevb.107.l140505

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