Nonreciprocal electronic transport in PdCrO2: Implication of spatial inversion symmetry breaking

Noncollinear spin structures, such as helimagnetic structures, have been gathering attention because of their nontrivial magnetic transport induced by topological effects. For a precise determination of spin structure, in addition to traditional neutron diffraction measurements, the time-reversal-odd rectification of electronic transport, which is referred to as nonreciprocal electronic transport, provides useful information because of the symmetry sensitivity. We observed nonreciprocal electronic transport below the Néel temperature in an itinerant antiferromagnet, PdCrO2, with a 120 spin structure. This implies breaking of spatial inversion symmetry owing to the magnetic ordering. Possible spin structures are discussed based on the magnetic field dependence of nonreciprocal transport.