Thermopower and Thermally Induced Domain Wall Motion in (Ga,Mn)As

Abstract

We study two reciprocal thermal effects in the ferromagnetic semiconductor (Ga,Mn)As by scattering theory: domain wall motion induced by a temperature gradient as well as heat currents pumped by a moving domain wall. The effective out-of-plane thermal spin transfer torque parameter $P_Q{\beta }_Q$, which governs the coupling between heat currents and a magnetic texture, is found to be of the order of unity. Unpinned domain walls are predicted to move at speed 10 m/s in temperature gradients of the order 10 $K/\mu \mathrm{m}$. The cooling power of a moving domain wall only compensates the heating due to friction losses at ultra-low domain wall velocities of about 0.07 m/s. The Seebeck coefficient is found to be of the order 100-500 $\mu V/K$ at T=10 K, in good agreement with recent experiment.

5 pages, 3 figures. Final version accepted by "Special issue: Caloritronics" in Solid State Communications

References in corpus (13)

• Theory of ferromagnetic (III,Mn)V semiconductors
• Microscopic approach to current-driven domain wall dynamics
• Thermal Spin-Transfer Torques in Magnetoelectronic Devices
• Mott Relation for Anomalous Hall and Nernst effects in Ga1-xMnxAs Ferromagnetic Semiconductors
• Microscopic Calculation of Spin Torques in Disordered Ferromagnets
• Theory of current-driven magnetization dynamics in inhomogeneous ferromagnets
• Spin Pumping of Current in Non-Uniform Conducting Magnets
• Nanoscale Magnetic Heat Pumps and Engines
• Thermoelectric spin transfer in textured magnets
• Field-Driven Domain-Wall Dynamics in GaMnAs Films with Perpendicular Anisotropy
• Creep of current-driven domain-wall lines: intrinsic versus extrinsic pinning
• Intrinsic Coupling between Current and Domain Wall Motion in (Ga,Mn)As
• Magnetocaloritronic nanomachines

Cited by in corpus (11)

• Spin Caloritronics
• Thermomagnonic spin transfer and Peltier effects in insulating magnets
• Helicity-dependent all-optical domain wall motion in ferromagnetic thin films
• Skyrmionic spin Seebeck effect via dissipative thermomagnonic torques
• Spin motive force induced by Rashba interaction in the strong sd coupling regime
• Thermal vector potential theory of magnon-driven magnetization dynamics
• Thermally driven domain wall motion in Fe on W(1 1 0)
• Topological spin transport by Brownian diffusion of domain walls
• Magnetocaloritronic nanomachines
• Thermally induced spin-transfer torques in superconductor/ferromagnet bilayers
• Microscopic calculation of thermally-induced spin-transfer torques