Spin-transfer torque and domain wall dynamics induced by triplet supercurrent

We theoretically study spin-transfer torques induced by a spin-triplet supercurrent in a magnet in proximity to a triplet superconductor. We show that spin-triplet correlations change the spin-transfer process and realize new types of torques, which are analogous to the adiabatic and nonadiabatic torques (beta term), without extrinsic spin-flip scattering. Remarkable advantages compared to conventional spin-transfer torques are highlighted in domain-wall manipulation. Oscillatory motions of a domain wall do not occur for a small Gilbert damping, and the threshold current density to drive its motion becomes zero in the absence of extrinsic pinning potentials due to the nonadiabatic torque controlled by the triplet correlations.