Temperature dependence of the magnetic penetration depth in BKBO superconductor
arXiv:cond-mat/0312334 · doi:10.1016/j.physc.2003.12.007
Abstract
Temperature dependence of the magnetic penetration depth, $λ$(T), was measured in the Meissner state in single crystals B$_{1-x}$K$_{x}$BiO$_{3}$ (x=0.37) using tunnel diode resonator technique. At low temperatures, $0.013 \le T/T_c \le 0.4$, $λ$(T) is exponentially flat, which provides a strong evidence for conventional s-wave BCS behavior. Numerical analysis of the data rules out the possibility of a gap with nodes.