Atomistic simulation of sub-nanosecond non-equilibrium field cooling processes for magnetic data storage applications

TL;DR

This study uses atomistic spin simulations to analyze rapid, non-equilibrium magnetic field cooling processes crucial for high-speed magnetic data storage, emphasizing the importance of heating to the Curie temperature and applying strong magnetic fields.

Contribution

It introduces an atomistic simulation approach to model sub-nanosecond thermally assisted magnetic writing processes, highlighting the physics of rapid heating and magnetic field requirements.

Findings

Heating to the Curie temperature shortens magnetic relaxation time.

Large magnetic fields are necessary for high thermoremanent magnetization.

Fast cooling processes require specific thermal and magnetic conditions.

Abstract

Thermally assisted magnetic writing is an important technology utilizing temperature dependent magnetic properties to enable orientation of a magnetic data storage medium. Using an atomistic spin model we study non-equilibrium field cooled magnetization processes on sub-nanosecond timescales required for device applications. We encapsulate the essential physics of the process in a TRM-T curve and show that for fast timescales heating to the Curie temperature is necessary where the magnetic relaxation time is shortest. Furthermore we demonstrate the requirement for large magnetic fields to achieve a high thermoremanent magnetization necessary for fast recording or data rates.