Using micromagnetic simulations, we study the interplay between strongly voltage-controlled magnetic anisotropy (VCMA), 200 kJ/m3, and gate width, 10–400 nm, in voltage-gated W/CoFeB/MgO based nano-constriction spin Hall nano-oscillators. The VCMA modifies the local magnetic properties such that the magnetodynamics transitions between regimes of (i) confinement, (ii) tuning, and (iii) separation with qualitatively different behaviors. We find that the strongest tuning is achieved for gate widths of the same size as the constriction width, for which the effective damping can be increased an order of magnitude compared to its intrinsic value. As a consequence, voltage control remains efficient over a very large frequency range, and subsequent manufacturing advances could allow spin Hall nano-oscillators to be easily integrated into next-generation electronics for further fundamental studies and industrial applications.
Voltage control of frequency, effective damping, and threshold current in nano-constriction-based spin Hall nano-oscillators
Note: This paper is part of the APL Special Collection on Magneto-ionic and electrostatic gating of magnetism: Phenomena and devices.
Victor H. González, Roman Khymyn, Himanshu Fulara, Ahmad A. Awad, Johan Åkerman; Voltage control of frequency, effective damping, and threshold current in nano-constriction-based spin Hall nano-oscillators. Appl. Phys. Lett. 19 December 2022; 121 (25): 252404. https://doi.org/10.1063/5.0128786
Download citation file: