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arXiv · 2102.08652

Effective magnetic monopole mechanism for localized electron pairing in HTS

Abstract

The mechanism responsible for spatially localized, strong coupling electron pairing characteristic of high-temperature superconductors (HTS) remains elusive and is a subject of hot debate. Here we propose a new HTS pairing mechanism which is the binding of two electrons residing in adjacent conducting planes of layered HTS materials by effective magnetic monopoles forming between these planes. The pairs localized near the monopoles form real-space seeds for superconducting droplets and strong coupling is due to the topological Dirac quantization condition. The pairing occurs well above the superconducting transition temperature Tc. Localized electron pairing around effective monopoles promotes, upon cooling, the formation of superconducting droplets connected by Josephson links. Global superconductivity arises when strongly coupled granules form an infinite cluster, and global superconducting phase coherence sets in. The resulting Tc is estimated to fall in the range from hundred to thousand Kelvins. Our findings pave the way for tailoring materials with elevated superconducting transition temperatures.

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M. C. Diamantini, C. A. Trugenberger, V. M. Vinokur. 2021-02-17. Effective magnetic monopole mechanism for localized electron pairing in HTS. https://arxiv.org/abs/2102.08652

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