Physics – Condensed Matter – Disordered Systems and Neural Networks
Scientific paper
2007-05-08
Phys. Rev. B 77, 054422 (2008)
Physics
Condensed Matter
Disordered Systems and Neural Networks
13 pages, 9 figures
Scientific paper
10.1103/PhysRevB.77.054422
We present a numerical study of the $\Delta H(M,\Delta M)$ method and its ability to accurately determine intrinsic switching field distributions in interacting granular magnetic materials such as perpendicular recording media. In particular, we study how this methodology fails for large ferromagnetic inter-granular interactions, at which point the associated strongly correlated magnetization reversal cannot be properly represented by the mean-field approximation, upon which the $\Delta H(M,\Delta M)$ method is based. In this study, we use a 2-dimensional array of symmetric hysterons that have an intrinsic switching field distribution of standard deviation $\sigma$ and ferromagnetic nearest-neighbor interactions $J$. We find the $\Delta H(M,\Delta M)$ method to be very accurate for small $J/\sigma$ values, while substantial errors develop once the effective exchange field becomes comparable with $\sigma$, corroborating earlier results from micromagnetic simulations. We furthermore demonstrate that this failure is correlated with deviations from data set redundancy, which is a key property of the mean-field approximation. Thus, the $\Delta H(M,\Delta M)$ method fails in a well defined and quantifiable manner that can be easily assessed from the data sets alone.
Berger Adam
Dahmen Karin A.
Liu Yang
No associations
LandOfFree
Determination of intrinsic switching field distributions in perpendicular recording media: numerical study of the $ΔH(M, ΔM)$ method does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Determination of intrinsic switching field distributions in perpendicular recording media: numerical study of the $ΔH(M, ΔM)$ method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Determination of intrinsic switching field distributions in perpendicular recording media: numerical study of the $ΔH(M, ΔM)$ method will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-153851