We theoretically investigate emergent impedance induced by domain wall (DW) dynamics in antiferromagnets (AFMs). Emergent impedance, arising from a combined action of spin-transfer torque and spinmotive force, was previously predicted and observed in spiral magnets. Here, we develop a formalism for the electrical response of an AFM DW under ac currents and obtain analytical expressions for the resulting emergent impedance. We find that two dynamical modes play separate roles in the emergent impedance: Translational motion of the DW center generates a contribution proportional to its velocity, analogous to that arising from the corresponding motion of a spiral magnet. Another contribution, unique to AFM DWs, originates from the time-dependent canting of the sublattice magnetizations localized within the moving DW, whose magnitude is inversely proportional to the AFM exchange coupling constant. The competition between these two distinct contributions determines the sign and magnitude of the imaginary part of the emergent impedance at subresonant frequencies. Our results provide fundamental insight into electron transport in AFMs and open avenues for AFM-based spintronics devices.

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• Antiferromagnetism
• Domain walls
• Spin torque
• Spintronics