Anti-ferromagnetic coupling effects on energy barrier and reversal properties of recording media

Abstract

Analytical solutions for coercivity HCM1, HCM2, effective (Mrt)eff, energy-harrier and effective thermal stability factor as a function of coupling constant J and other film parameters have been derived for two coupled ferromagnetic layers (FM-FM layer) with different magnetic properties for the first time. The condition for reduced effective (Mrt)eff is analyzed. These results are valuable for laminated antiferromagnetically coupled media design. This may open up a channel to raise thermal stability significantly while maintaining lower noise for longitudinal recording media.