Muon spin rotation study of the ternary noncentrosymmetric superconductors Li$_2$Pd$_x$Pt$_{3-x}$B

Petra S. Häfliger; Rustem Khasanov; Rolf Lortz; Alexander Petrović; Kazumasa Togano; Chris Baines; Bijörn Graneli; Hugo Keller

paper

Muon spin rotation study of the ternary noncentrosymmetric superconductors Li $_{2}$ Pd $_{x}$ Pt $_{3 - x}$ B

arXiv:0709.3777

Abstract

We investigated the superconducting state of the noncentrosymmetric superconductors Li $_{2}$ Pd $_{x}$ Pt $_{3 - x}$ B with superconducting transition temperature $T_{c}$ = 5.16(8) K ( $x$ =2.25), 3.56(8) K ( $x = 1.5$ ) and 2.60 K ( $x = 0$ ) by means of muon-spin rotation ( $μ$ SR) and specific heat experiments. The $μ$ SR relaxation rate $σ_{sc}$ was found to be constant at low temperatures for all the compounds. Data taken at different magnetic fields show that the magnetic penetration depth $λ$ is field-independent for Li $_{2}$ Pd $_{2.25}$ Pt $_{0.75}$ B and Li $_{2}$ Pt $_{3}$ B. The electronic contribution to the specific heat measured in Li $_{2}$ Pd $_{1.5}$ Pt $_{1.5}$ B and Li $_{2}$ Pt $_{3}$ B increases exponentially at the lowest temperatures. These features suggest that the {\it whole family} of Li $_{2}$ Pd $_{x}$ Pt $_{3 - x}$ B are single-gap s-wave superconductors across the entire doping regime.

10 pages, 3 figures

Muon spin rotation study of the ternary noncentrosymmetric superconductors Li2​Pdx​Pt3−x​B

Abstract

Muon spin rotation study of the ternary noncentrosymmetric superconductors Li $_{2}$ Pd $_{x}$ Pt $_{3 - x}$ B