Minimization of the Switching Time of a Synthetic Free Layer in Thermally Assisted Spin Torque Switching

TL;DR

This paper theoretically analyzes how to minimize switching time in thermally assisted spin torque switching of synthetic free layers, identifying key conditions and methods to determine coupling fields for optimal performance.

Contribution

It introduces a condition for minimizing switching time and proposes a way to determine the coupling field from resonance frequencies, advancing understanding of spin torque switching.

Findings

Switching time is minimized when H_J=|H_s|/(2 alpha).

Coupling field can be determined from resonance frequencies.

Provides theoretical insights into optimizing spin torque switching.

Abstract

We theoretically studied the thermally assisted spin torque switching of a synthetic free layer and showed that the switching time is minimized if the condition H_J=|H_s|/(2 alpha) is satisfied, where H_J, H_s and alpha are the coupling field of two ferromagnetic layers, the amplitude of the spin torque, and the Gilbert damping constant. We also showed that the coupling field of the synthetic free layer can be determined from the resonance frequencies of the spin-torque diode effect.