London penetration depth at zero temperature and near superconducting transition

Abstract

A simple relation is established between the zero-$T$ penetration depth $\lambda (0)$ and the slope of ${\lambda }^{-2}(T)$ near $T_c$, similar to Helfand-Werthamer's relation for $H_{c2}(0)$ and the slope of $H_{c2}(T)$ at $T_c$ for the isotropic s-wave case with non-magnetic scattering.\cite{HW} When the scattering parameter $\rho =\hslash v/2\pi T_c\ell$ ($v$ is the Fermi velocity and $\ell$ is the mean-free path) varies from 1 to 10, the coefficient of proportionality between ${\lambda }^{-2}(0)$ and $T_c(d{\lambda }^{-2}/dT{)}_{T_c}$ changes from 0.43 to 0.38. Combining this relation with the Rutgers thermodynamic identity, one can express $\lambda (0)$ in terms of the slope $(d{H}_{c2}/dT{)}_{T_c}$ and the density of states.

References in corpus (2)

• Doping evolution of the absolute value of the London penetration depth and superfluid density in single crystals of Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Evolution of London penetration depth with scattering in single crystals of K${}_{1-x}$Na${}_x$Fe${}_2$As${}_2$

Cited by in corpus (2)

• Investigating the superconducting state of 2$H$-NbS${}_2$ as seen by the vortex lattice
• Two characteristic contributions to the superconducting state of 2$H$-NbSe${}_2$