Data distortion due to magnetic medium microstructure

We investigate the effect of a medium's magnetic microstructure on the recording of digital data, We record magnetic transitions at different spatial positions and look for repeatable shifts from the intended locations, We account for nonrepeatable effects and find experimentally that medium-induced repeatable shifts can be larger than 50 nm, We conclude from these results that the repeatable shifts arise from the medium's microstructure which remains fixed after fabrication.