Writing of high-density patterned perpendicular media with a conventional longitudinal recording head

Abstract

We have fabricated arrays of magnetic islands in perpendicular CoCrPt media with ∼100 nm lateral dimension using a focused ion beam. A quasistatic write/read tester was used to study aspects of the recording physics of these patterned media. We present results on the variation of the readback signal as the phase of the written square wave changes with respect to the patterned array as a function of island size and write current. Using an analytic near-field expression for head field we are able to model how the observed dependence between phase shift and readback signal as a function of write current arises. This analysis allows us to gain an insight into the role of the island switching field distribution and the write head magnetic field gradient in the patterned media writing process.