Role of spin-transfer torques on synchronization and resonance phenomena in stochastic magnetic oscillators

Abstract

A theoretical study on how synchronization and resonance-like phenomena in superparamagnetic tunnel junctions can be driven by spin-transfer torques is presented. We examine the magnetization of a superparamagnetic free layer that reverses randomly between two well-defined orientations due to thermal fluctuations, acting as a stochastic oscillator. When subject to an external ac forcing this system can present stochastic resonance and noise-enhanced synchronization. We focus on the roles of the mutually perpendicular damping-like and field-like torques, showing that the response of the system is very different at low and high-frequencies. We also demonstrate that the field-like torque can increase the efficiency of the current-driven forcing, specially at sub-threshold electric currents. These results can be useful for possible low-power, more energy efficient, applications.

arXiv comment9 pages, 7 figures

References in corpus (8)

• Measurement of the Spin-Transfer-Torque Vector in Magnetic Tunnel Junctions
• Spin torque building blocks
• Magnetization dynamics with a spin-transfer torque
• Frequency and Phase Synchronization in Stochastic Systems
• Stochastic resonance of a nanomagnet excited by spin transfer torque
• Thermal Relaxation Rates of Magnetic Nanoparticles in the Presence of Magnetic Fields and Spin-Transfer Effects
• Micromagnetic understanding of stochastic resonance driven by spin-transfertorque
• Spin-Torque Diode Measurements of MgO-Based Magnetic Tunnel Junctions with Asymmetric Electrodes

Cited by in corpus (2)

• Low Barrier Nanomagnets as p-bits for Spin Logic
• Magnetization reversal driven by low dimensional chaos in a nanoscale ferromagnet