Spin transfer and spin-orbit torques in in-plane magnetized (Ga,Mn)As tracks

L. Thevenard (1, 2) , Benoit Boutigny (1, 2) , Nicholas Güsken (1, 2) , Loic Becerra (1, 2) , Christian Ulysse (3) , Sylvain Shihab (1, 2) , Aristide Lemaître (3) , Joo-Von Kim (3) , Vincent Jeudy (4) , Catherine Gourdon (1, 2)

1 INSP - Institut des Nanosciences de Paris
2 INSP-E1 - Nanostructures et systèmes quantiques
3 C2N - Centre de Nanosciences et de Nanotechnologies [Marcoussis]
4 LPS - Laboratoire de Physique des Solides

Current-driven domain wall motion is investigated experimentally in in-plane magnetized (Ga,Mn)As tracks. The wall dynamics is found to differ in two important ways with respect to perpendicularly magnetized (Ga,Mn)As: the wall mobilities are up to ten times higher and the walls move in the same direction as the hole current. We demonstrate that these observations cannot be explained by spin-orbit field torques (Rashba and Dresselhaus types) but are consistent with nonadiabatic spin transfer torque enhanced by the strong spin-orbit coupling of (Ga,Mn)As. This mechanism opens the way to domain wall motion driven by bulk rather than interfacial spin-orbit coupling as in ultrathin ferromagnet/heavy metal multilayers.

Mots clés: Spin-orbit torque; domain wall motion; GaMnAs thin films; Kerr microscopy; Spin transfer torque

Mots clés: propagation de parois de domaines

Domaines: Physique Générale [physics.gen-ph]

L. Thevenard, Benoit Boutigny, Nicholas Güsken, Loic Becerra, Christian Ulysse, et al.. Spin transfer and spin-orbit torques in in-plane magnetized (Ga,Mn)As tracks. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2017, 95, pp.54422 - 54422. ⟨10.1103/PhysRevB.95.054422⟩. ⟨hal-01470215⟩