Superconductivity in noncentrosymmetric YPtBi under pressure

Abstract

We report a high-pressure single-crystal study of the noncentrosymmetric superconductor YPtBi (${T}_{c}=0.77$ K). Magnetotransport measurements show a weak metallic behavior with a carrier concentration $n\ensuremath{\simeq}2.2\ifmmode\times\else\texttimes\fi{}{10}^{19}$ cm${}^{\ensuremath{-}3}$. Resistivity measurements up to $p=2.51$ GPa reveal superconductivity is promoted by pressure. The reduced upper critical field ${B}_{c2}(T)$ curves collapse onto a single curve, with values that exceed the model values for spin-singlet superconductivity. The ${B}_{c2}$ data point to an odd-parity component in the superconducting order parameter, in accordance with predictions for noncentrosymmetric superconductors.