Micromagnetic simulations based on the Landau-Lifshitz-Gilbert equation are presented to study spin-polarized current induced magnetization switching in asymmetric nanoring-shaped magnetic tunnel junctions. The results show that in a nanoring with an intermediate eccentric distance S, the critical switching voltage VCreaches the minimum whose magnitude is less than half of the voltage for a symmetric nanoring. In addition to the spin-transfer torque, the current induced Ampère field is found to play a crucial part in the switching process. Analysis is given to explain the existence of such an energy valley that leads to the minimal voltage. © 2009 Elsevier B.V. All rights reserved.
Xu, H. Z., Chen, X., Hua, J., & Liu, J. M. (2009). Minimal switching voltage for magnetization reversals in asymmetric nanorings. Journal of Magnetism and Magnetic Materials, 321(22), 3698–3701. https://doi.org/10.1016/j.jmmm.2009.07.018