HAMR switching dynamics and the magnetic recording quadrilemma

M. Strungaru*, B. T. Nguyen, K. Yuanmae, R. F.L. Evans, R. W. Chantrell, P. Chureemart, J. Chureemart

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


We investigate the dynamical switching process of Heat Assisted Magnetic Recording (HAMR) by numerical calculations of switching probability using an atomistic model. Calculations show that at the elevated write temperature of HAMR there is a loss of information arising from ’backswitching’: a thermodynamic phenomenon which comes into play when the ratio of the Zeeman energy to the thermal energy is insufficiently large to completely stabilise the switched direction. We consider the special case of Heated Dot Magnetic Recording, where a reduction of switching probability can be related to a bit error rate. We show that the backswitching becomes more pronounced at faster write times. Also, we show that in the case of current recording media, based on the binary alloy FePt, backswitching will be a more stringent limitation on recording density than the usually assumed thermal stability criterion.

Original languageEnglish
Article number170041
Number of pages8
JournalJournal of Magnetism and Magnetic Materials
Early online date20 Oct 2022
Publication statusPublished - 15 Dec 2022

Bibliographical note

© 2022 The Authors


  • Bit error rate
  • Heat-Assisted Magnetic Recording
  • Heated Dot Magnetic Recording
  • Magnetisation switching

Cite this