We present 11B nuclear magnetic resonance (NMR) measurements in superconductors Li2(Pd,Pt)3B without inversion symmetry. In Li2Pd3B, the spin lattice relaxation rate 1/T 1 shows a well-defined coherence peak below Tc, and follows an exponential temperature variation exp(-Δ/kBT) at low temperatures. At a magnetic field of 1.46 T, the energy gap Δ was found to be 1.1kBTc, but it recovers to 1.5kBT c at a field of 0.44 T, which is quite close to the value 1.75k BTc for a weak coupling BCS superconductor. This behavior is in contrast to that found in Li2Pt3B where 1/T 1 is proportional to T3, and the difference between the two compounds is ascribed to the different strength of spin orbit coupling.
ASJC Scopus subject areas
- Physics and Astronomy(all)