Landau–Lifshitz–Gilbert Micromagnetic Analysis of Single-Pole-Type Write Head for Perpendicular Magnetic Recording Using Full-FFT Program on PC Cluster System

A Landau-Lifshitz-Gilbert (LLG) micromagnetic analysis using a parallelized program on a PC cluster is investigated. In the analysis, the whole magnetic material is treated micromagnetically using the LLG equation. The fast Fourier transform (FFT) algorithm is incorporated in the head region in addition to the medium region to derive the demagnetization field and the program is parallelized using the message passing interface (MPI). The PC cluster system with 8 CPU has achieved a calculation speed 4800 times faster than our original program on a single 64-bit processor system. Quasi-static field distributions for a single-pole type (SPT) are derived and the accuracy is validated by comparison with the finite-element method (FEM). Finally, dynamic responses are derived for various head structures and materials.