Domain Wall Assisted Magnetic Recording

TL;DR

This paper explores how domain wall assisted switching in composite magnetic media can significantly reduce switching fields and increase data storage density, using micromagnetic simulations and analytical models.

Contribution

It introduces the concept of domain wall assisted magnetic recording (DWAMR) and demonstrates its potential to triple areal density compared to traditional methods.

Findings

Up to three-fold increase in areal density with DWAMR.

Significant reduction in switching fields via domain wall mechanisms.

Maintains thermal stability while reducing switching energy.

Abstract

Using numerical and analytical micromagnetics we calculated the switching fields and energy barriers of the composite (exchange spring) magnetic recording media, which consist of layers with high and low magnetocrystalline anisotropy. We demonstrate that the ultimate potential of the composite media is realized if the interfacial domain wall fits inside the layers. The switching occurs via domain wall nucleation, compression in the applied field, de-pinning and propagation through the hard/soft interface. This domain wall assisted switching results in a significant reduction of the switching field without substantial decrease of the for thermal activation energy barrier. We demonstrate that the Domain Wall Assisted Magnetic Recording (DWAMR) offers up to a three-fold areal density gain over conventional single layer recording.