Full Control of the Spin-Wave Damping in a Magnetic Insulator Using Spin-Orbit Torque

A. Hamadeh (1) , O. D’allivy Kelly (2) , C. Hahn (1) , H. Meley (1) , R. Bernard (2) , A. Molpeceres (2) , V. Naletov (1, 2) , M. Viret (1) , A. Anane (2) , V. Cros (2) , O. Demokritov , J. l. Prieto (3) , M. Muñoz (3) , G. de Loubens (1) , O. Klein (4, 1)

1 LNO - Laboratoire Nano-Magnétisme et Oxydes
2 Laboratoire Albert Fert (ex-UMPhy Unité mixte de physique CNRS/Thales)
3 Instituto de Sistemas Optoelectrónicos y Microtecnología
4 SPINTEC - SPINtronique et TEchnologie des Composants

It is demonstrated that the threshold current for damping compensation can be reached in a 5  μm diameter YIG(20  nm)|Pt(7  nm) disk. The demonstration rests upon the measurement of the ferromagnetic resonance linewidth as a function of Idc using a magnetic resonance force microscope (MRFM). It is shown that the magnetic losses of spin-wave modes existing in the magnetic insulator can be reduced or enhanced by at least a factor of 5 depending on the polarity and intensity of an in-plane dc current Idc flowing through the adjacent normal metal with strong spin-orbit interaction. Complete compensation of the damping of the fundamental mode by spin-orbit torque is reached for a current density of ∼3×1011  A⋅m−2, in agreement with theoretical predictions. At this critical threshold the MRFM detects a small change of static magnetization, a behavior consistent with the onset of an auto-oscillation regime

Domaines: Physique [physics]

A. Hamadeh, O. D’allivy Kelly, C. Hahn, H. Meley, R. Bernard, et al.. Full Control of the Spin-Wave Damping in a Magnetic Insulator Using Spin-Orbit Torque. Physical Review Letters, 2014, 113 (19), pp.197203. ⟨10.1103/PhysRevLett.113.197203⟩. ⟨cea-01377085⟩