Positive magnetoresistance in anapole superconductor junctions

This paper presents a method to detect time-reversal symmetry breaking in noncentrosymmetric superconductors using only transport measurements. Specifically, if time-reversal symmetry is broken via a phase difference between singlet and triplet correlations, as in anapole superconductors, the differential conductance in superconductor-ferromagnet-normal metal junctions is enhanced by increasing the exchange field strength in the ferromagnet. This is in sharp contrast with the negative magnetoresistance when using superconductors in which time-reversal symmetry is preserved. Moreover, results show a large quadrupolar component of the magnetoresistance which is qualitatively different from the bipolar giant magnetoresistance in strong ferromagnets.