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arXiv · 1807.03866

Impact of $e-e$ interactions on the superfluid density of dirty superconductors

V. A. Khodel·J. W. Clark·M. V. Zverev
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Abstract

Landau's theory of the Fermi liquid is adapted to analyze the impact of electron-electron ($e-e$) interactions on the deficit of the superfluid density $ρ_{s0}=ρ_s(T=0)$ in dirty superconducting electron systems in which the damping $γ$ of single-particle excitations exceeds the zero temperature BCS gap $Δ_0$. In the dirty strong-coupling limit $γ/Δ_0\gg 1,m^*/m_e\gg 1$, the formula derived for $ρ_{s0}$ is shown to coincide with the well-known empirical Uemura relation provided pair-breaking contributions are nonexistent. The roles of the crystal lattice and magnetic pair-breaking effects in the observed decline of the zero-temperature superfluid density $ρ_{s0}$ in overdoped LSCO compounds are also discussed. Our method is also applied to elucidation of results from the pioneering experimental studies performed recently by Bozovic and collaborators in overdoped LSCO compounds.

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V. A. Khodel, J. W. Clark, M. V. Zverev. 2019-03-21. Impact of $e-e$ interactions on the superfluid density of dirty superconductors. https://doi.org/10.1103/physrevb.99.184503

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