Micromagnetics-related papers

Micromagnetics-related papers of Visscher group

"Quaternion-based algorithm for micromagnetics", P. B. Visscher and Xuebing Feng, Phys. Rev. B 65, 104412 (2002), pdf file.
"Coarse-Graining Landau-Lifshitz damping", Xuebing Feng and P. B. Visscher, vol. 89, p. 6988, J. Appl. Physics (2001), pdf file.
"Stability and Accuracy of Micromagnetic Algorithms with Thermal Noise", Xuebing Feng and P. B. Visscher, J. Appl. Phys. 91 8712 (2002). [Proceedings of Nov. 2001 MMM Conference # HE-01] pdf file, link to journal's better pdf.
"Visualization of spin waves during switching simulation", P. B. Visscher, O. Traistaru, D. M. Apalkov, and Xuebing Feng, J. Appl. Phys. 91, 7544 (2002), Proceedings of Nov. 2001 MMM Conference, paper # DF-01, available from this AIP link or this pdf file,
"Simulation of thermal ripple in thin films: 'Roller-coaster' visualization", Xuebing Feng, P. B. Visscher, and D. M. Apalkov, J. Appl. Phys. v. 93, p. 8020 (2003), available from this AIP link or this pdf file.
"Simple Recursive Cartesian Implementation of Fast Multipole Algorithm", P. B. Visscher and D. M. Apalkov, Journal of Magnetism and Magnetic Materials 322 (2010) 275-281. (doi:10.1016/j.jmmm.2009.09.033)

The abovementioned J. Appl. Phys. preprints are copyrighted by the American Institute of Physics. They may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.

PDF preprints: some of the following pdf preprints are made from LaTeX and have a bad screen font, but print out ok:

"Switching Simulations in Perpendicular Media: Spin Wave Instabilities", P. B. Visscher, D. M. Apalkov, and Xuebing Feng, IEEE Trans. Mag. 38 2523-2525 (2003)., pdf file. (Related movies below)
"Simple iterative calculation of micromagnetic kernels", D. Apalkov and P. B. Visscher, J. Appl Phys. 93, 6808 (2003), pdf file.
"Application of fast multipole method to micromagnetic simulation of periodic systems", D. M. Apalkov and P. B. Visscher, accepted by IEEE Trans. Mag., June 2003, pdf file.
"Time-dependent remanent coercivity in fast switching simulations of perpendicular media", Arkajyoti Misra, P. B. Visscher, and D. Apalkov, J. Appl. Phys. Oct. 15, 2003, pdf file.
"Sweep-rate dependent coercivity simulation of FePt particle arrays", Xuebing Feng andP. B. Visscher, preprint, Oct. 2003, paper EG-06, MMM-Intermag Meeting, Anaheim, Jan. 2004, pdf file.
"Slonczewski spin-torque as negative damping: Fokker-Planck computation of switching rates", D. M. Apalkov and P. B. Visscher, submitted to MML 2004, Metallic Multilayers Symposium, Boulder, CO, pdf file.
"Spin-torque switching: Fokker-Planck rate calculation", D. M. Apalkov and P. B. Visscher, Phys. Rev. B 2005, (preprint at cond-mat 0405305, with derivation of Fokker-Planck equation and fit to telegraph noise data) pdf file.

Movies (Quicktime .mov) related to switching

Tutorial on micromagnetics (power point + movies of LLG dynamics, especially for switching).

Current-driven switching (Slonczewski mechanism). Side view of thick (lower) and thin (upper) Co layers before switching. movie 6 MB.

Demo of k-space spin wave visualization (single spin wave, k along z axis) real space movie 1 MB, k-space movie 3 MB.

Demo of 3 spin waves, k-space 0.5 MB .mov file.

Spin wave visualization of switching instability (k-space on left, r-space on right): .mov file, 4MB.

Switching by head field (perpendicular media) -- head moves past grain (movie with explanation available; for further details see 2002 Intermag paper GV-03 cited above.

Nanosecond switching of perpendicular media (movie with explanation available; for further details see preprint cited above.

Hysteresis loop in self-assembled FePt nanoparticle array. Movie shows 32 spherical 4 nm particles (though displayed as squares) separated by 6 nm (center-to-center) in hexagonal array, H_K=15 kOe, M vectors in red, easy axes in blue, traces hysteresis loop on MH graph, 8 MB .mov file.

Animations of MRAM switching and hysteresis of SAF bilayer, produced by NSF REU (Research Experiences for Undergraduates) students.

Magnetization dynamics in permalloy

Simulation of NIST experiment with roller-coaster movie

Collaboration with ORNL

"On the role of magnetostatic interactions in assemblies of Fe nanoparticles", T. C. Schulthess (Oak Ridge National Laboratory), M. Benakli (Maxtor Corp.), P. B. Visscher (University of Alabama), K. D. Sorge, J. R. Thompson, F. A. Modine, T. E. Haynes, L. A. Boatner, G. M. Stocks, and W. H. Butler (ORNL) abstract of talk at 2001 March Meeting.