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Shingled perpendicular magnetic recording is one of the candidates for achieving areal recording densities of 1 terabit per square inch and above in next generation magnetic recording. It is assumed that shingled recording would not require a big change in head and media design. Shingled recording uses a write head with wide pole and an extended conventional continuous recording medium. Written tracks partially overwrite adjacent data with a certain track pitch. With the help of the wide pole tip, the write head can generate a large recording field, which resolves the so-called trilemma. The down-side of shingled recording is that a new architecture should be introduced to ensure random access, which is mandatory in hard disk drives. In this article, head and media simulations of shingled recording are surveyed. Experimental results and the issues to be solved are also reviewed.

Analysis of the recording field and magnetization of recording write heads is surveyed as part of a series of articles entitled Applications of Micromagnetics to Magnetic Recording. The present article discusses the speed-up of Landau-Lifshitz-Gilbert (LLG) micromagnetic calculations. In particular, parallelization of the analysis code, introduction of three-dimensional fast-Fourier-transform (FFT), FFT reduction procedures, and storage of the data in binary form are described. Reducing the calculation memory in FFT is important as well as computing speed. The necessity of introducing the FFT is also discussed with regard to the calculation speed for practical applications. Finally, methods to generate the finite-difference cells and to derive the coil field are described.

Recording field and magnetization analysis of recording write heads is surveyed as a series of application of micromagnetics to magnetic recording. In this article, write head modeling with various methods, the necessity of self-consistent analysis, and speed-up of Landau-Lifshitz-Gilbert (LLG) micromagnetic caluculations are discussed.

In the first half, recording fields of single-pole-type head were derived by using FEM simulations, then, various media were considered and written track widths, erase bands, SNR’s, and written bit patterns were derived from Landau-Lifshitz- Gilbert (LLG) simulations. In the second part, full LLG calculations considering the SPT head with side shields and double-layered medium were carried out and the magnetization patterns and the recording fields were derived.