H. Tou et al., ODD-PARITY SUPERCONDUCTIVITY WITH PARALLEL SPIN PAIRING IN UPT3 - EVIDENCE FROM PT-195 KNIGHT-SHIFT STUDY, Physical review letters, 77(7), 1996, pp. 1374-1377
The temperature dependence of the Pt-195 Knight shift, K, for the high
quality single crystal UPt3 has been measured down to T = 28 mK in ap
plied magnetic fields parallel and perpendicular to the hexagonal c ax
is. No change of K's has been found across the superconducting transit
ion temperature T-c down to 28 mK regardless of the crystal directions
and independent of the superconducting multiphases. It is demonstrate
d that UPt3 is the odd-parity superconductor with parallel spin pairin
g following the direction of the magnetic field in a range of 4.4-15.6
kOe without an appreciable pinning of the order parameter to the latt
ice.