Manipulating Transient SOT-MRAM Switching Dynamics for Efficiency Improvement and Probabilistic Switching
This paper explores the transient dynamics involved in switching spin-orbit torque magnetic random-access memory (SOT-MRAM) devices stabilized by in-plane uniaxial magnetocrystalline anisotropy. A theoretical model is developed to describe the interaction between spin torques and effective fields during magnetization writing, helping to identify areas of successful and failed switching.
Quasi-Stochastic Switching Regime
The study highlights a “quasi-stochastic” regime that exists between deterministic failed and successful switching. This regime arises from the competition between torque-driven and precession-driven magnetization changes during the switching process.
Device Optimization for Lower Current and Faster Switching
- Minor adjustments to device geometry, materials, and electrical inputs leverage transient effects to reduce the switching barrier.
- This enables SOT-MRAM switching with much lower currents and faster write speeds than conventional designs.
Probabilistic Switching at Elevated Temperatures
At higher temperatures, the unpredictable stochastic regime transforms into a controllable probabilistic “transition band.” This band features monotonic and tunable regions of probabilistic operation, allowing for refined control through electrical inputs.
Through this addition of control mechanisms through electrical inputs, our framework paves the way for the creation of a fast, efficient probabilistic bit (p-bit) for the field of probabilistic computing.
Author's Summary
The study presents methods to manipulate transient switching behaviors in SOT-MRAM, achieving faster, lower-power operation and enabling controllable probabilistic computing applications.