Effect of the Dimensions of a Stepped-Pole Writer on Side Erasure and Recording Performance

Micromagnetic simulations are used to investigate side erasure as a function of write transducer geometry for shingled recording on a non-oriented barium-ferrite particulate tape media without a soft-underlayer. A ring-type writer with a short stepped pole is shown to produce very little transition curvature compared to conventional writers and to almost eliminate the erase band at the shingled track edge. In addition, the effect of the stepped pole on side erasure is found to be essentially independent of the writer gap size. However, the dimensions of the stepped pole do affect the system recording performance and should not be selected arbitrarily. We find that intermediate stepped-pole lengths produce smaller broad-band signal-to-noise ratio (BB-SNR) than a conventional writer, or require much larger deep-gap fields, whereas writers with short stepped poles (typically below 100 nm) provide more than 1 dB BB-SNR uplift at 200 kfci for only a moderate increase of writer deep-gap field. Finally, we find that the effect of the stepped pole on write performance also depends on the writer gap size.