Control of spectral characteristics of spin-current auto-oscillator by electric field

Abstract

We study the effects of electrostatic gating on the magnetization auto-oscillations induced by the local injection of electric current into a ferromagnet/heavy metal bilayer. We find that the characteristic currents required for the excitation, the intensity and the spectral characteristics of the generated dynamical states can be tuned by the voltage applied to the metallic gate separated from the bilayer by a thin insulating layer. We show that the effect of electrostatic gating becomes enhanced in the strongly nonlinear oscillation regime at sufficiently large driving currents. Analysis shows that the observed effects are caused by a combination of electric field-dependent surface anisotropy and electric field-dependent contribution to the current-induced spin-orbit torques. The demonstrated ability to control the microwave emission and spectral characteristics provides an efficient approach to the development of electrically tunable microwave nano-oscillators.

6 pages, 4 figures

References in corpus (3)

• Lineshape distortion in a nonlinear auto-oscillator near generation threshold: Application to spin-torque nano-oscillators
• Spin-Torque Ferromagnetic Resonance Measurements of Damping in Nanomagnets
• Control of current-induced spin-orbit effects in a ferromagnetic heterostructure by electric field

Cited by in corpus (4)

• Giant voltage control of spin Hall nano-oscillator damping
• Fabrication of voltage gated spin Hall nano-oscillators
• Dynamical mode coupling and coherence in spin Hall nano-oscillator with perpendicular magnetic anisotropy
• Voltage control of frequency, effective damping and threshold current in nano-constriction-based spin Hall nano-oscillators