학술논문

Micromagnetic Simulations of Exchange-Coupled Core–Shell Particulate Media
Document Type
Periodical
Author
Source
IEEE Transactions on Magnetics IEEE Trans. Magn. Magnetics, IEEE Transactions on. 50(11):1-4 Nov, 2014
Subject
Fields, Waves and Electromagnetics
Magnetic cores
Media
Saturation magnetization
Magnetic recording
Atmospheric modeling
Magnetic hysteresis
Soft magnetic materials
Language
ISSN
0018-9464
1941-0069
Abstract
Micromagnetic simulations are used to investigate the reversal of exchange-coupled magnetic core–shell particles and their application to particulate tape recording. With thin soft magnetic shells, the reversal of the core–shell particle remains of Stoner–Wohlfarth type. We find that the thicker the shell or the higher its saturation magnetization, the larger the reduction of the particle switching field, in quantitative agreement with analytical predictions. Recording simulations are also performed for core/shell particulate media. This paper demonstrates that core–shell particles can provide broadband signal-to-noise ratio improvement over conventional single phase nanoparticles, while still satisfying thermal stability and writeability using conventional ring-type writers.