Turn‐On of Current‐Induced Spin Torque Upon Non‐collinear Antiferromagnetic Ordering in Delafossite PdCrO 2

Abstract Measurements of the current‐induced spin torque produced by the delafossite antiferromagnet PdCrO 2 and acting on an adjacent ferromagnetic permalloy layer are reported. The spin torque increases strongly as the temperature is reduced through the Néel temperature, when the PdCrO 2 transitions from a paramagnetic phase to a non‐collinear antiferromagnetic state. This result is qualitatively consistent with density functional theory calculations regarding how spin‐current generation changes upon antiferromagnetic ordering in PdCrO 2 .