Superfluid density of a pseudogapped superconductor near SIT

M. V. Feigel'man; L. B. Ioffe

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arXiv · 1509.05138

Superfluid density of a pseudogapped superconductor near SIT

M. V. Feigel'man·L. B. Ioffe

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Abstract

We analyze critical behavior of superfluid density $\rho_s$ in strongly disordered superconductors near superconductor-insulator transition and compare it with the behavior of the spectral gap $\Delta$ for collective excitations. We show that in contrast to conventional superconductors, the superconductors with preformed pairs display unusual scaling relation $\rho_s \propto \Delta^2$ close to superconductor-insulator transition. This relation have been reported in very recent experiments.

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M. V. Feigel'man, L. B. Ioffe. 2015-09-17. Superfluid density of a pseudogapped superconductor near SIT. https://arxiv.org/abs/1509.05138

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