Design of CF-SPT head having large recording field and small stray field using 3-D ON/OFF method

Koji Akiyama, Daisuke Miyagi, Norio Takahashi

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)


The optimal design of a magnetic recording head is one important issue for high magnetic recording of 600-Gb/in2and beyond. In this paper, a three-dimensional topology optimization method (ON/OFF method) combined with a finite-element method is applied for the optimization of a cusp field single-pole-type head. In the ON/OFF method, the unknown variable is the reluctivity of magnetic material in the design domain and there is no special constraint. Therefore, the possibility of finding more optimal topology is increased compared with the conventional optimization method in which the design variables are specified. The optimal shape and dimension of a head is determined so that the flux density in a recording bit becomes the maximum and the leakage flux in the adjacent bit and adjacent track becomes the minimum. The recording field of 1.75 T and the field gradient of 0.038 T/nm (380 Oe/nm) are obtained for the head-soft underlayer distance of 25 nm.

Original languageEnglish
Pages (from-to)2431-2433
Number of pages3
JournalIEEE Transactions on Magnetics
Issue number10
Publication statusPublished - 2006
Externally publishedYes


  • Finite-element analysis
  • magnetic recording
  • optimization

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering

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