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arXiv · 2106.10010

Density induced BCS-Bose evolution in gated two-dimensional superconductors: The Berezinskii-Kosterlitz-Thouless transition as a function of carrier density

Tingting Shi·Wei Zhang·C. A. R. Sa de Melo
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Abstract

We discuss the evolution from BCS to Bose superconductivity versus carrier density in gated two-dimensional s-wave superconductors. We show that the transition from the normal to the superconducting state is controlled by the Berezinskii-Kosterlitz-Thouless vortex-antivortex pairing mechanism, and that the evolution from high carrier density (BCS pairing) to low carrier density (Bose pairing) is just a crossover in s-wave systems. We compare our results to recent experiments on the superconductor LixZrNCl, a lithium intercalated layered nitride, and obtain very good quantitative agreement at low and intermediate densities.

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Tingting Shi, Wei Zhang, C. A. R. Sa de Melo. 2021-06-18. Density induced BCS-Bose evolution in gated two-dimensional superconductors: The Berezinskii-Kosterlitz-Thouless transition as a function of carrier density. https://arxiv.org/abs/2106.10010

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