Superfluid density in gapless superconductor CeCoIn(5).

Temperature dependence of the London penetration depth λ measured in single crystals of CeCoIn(5) is interpreted as being caused by a strong pair-breaking scattering that makes the superconductivity in this compound gapless. For a gapless d-wave superconductor, we derive λ = λ(0)(1-T(2)/T(c)(2))(-1/2) caused by the combined effect of magnetic and non-magnetic scattering, in excellent agreement with the data in the full temperature range and with the gapless s-wave case of Abrikosov and Gor'kov. We also obtain the slope of the upper critical field at T(c) that compares well with the measured slope.