We investigate the formation and dynamics of spin textures inantiferromagnetic insulators adjacent to a heavy-metal substrate with strongspin-orbit interactions. Exchange coupling to conduction electrons engenders aneffective anisotropy, Dzyaloshinskii-Moriya interactions, and a magnetoelectriceffect for the N\'{e}el order, which can conspire to produce nontrivialantiferromagnetic textures. Current-driven spin transfer enabled by the heavymetal, furthermore, triggers ultrafast (THz) oscillations of the N\'{e}el orderfor dc currents exceeding a critical threshold, opening up the possibility ofTerahertz spin-torque self-oscillators. For a commonly invokedantidamping-torque geometry, however, the instability current scales with theenergy gap of the antiferromagnetic insulator and, therefore, may bechallenging to reach experimentally. We propose an alternative generic geometryfor inducing ultrafast autonomous antiferromagnetic dynamics.
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