Read-head Conditions for Obtaining Areal Recording Density of 5.8 Tbit/in.2 on a Bit-Patterned Medium

Abstract

The optimum magneto-resistive read-head (MR head) conditions, namely, read track width (TWR) and shield gap (Gs), with a bit-patterned medium (BPM) for areal recording density of 5.8 Tbit/in.2 were determined by analytical calculation. Signal-to-noise ratio at a linear recording density of 1124 kfci (SNR1124kfci) and crosstalk were calculated in consideration of head noise, and optimum TWR and Gs were obtained from the calculation results. The effect of intertrack interference cancellation (ITIC) was investigated by using a signal-processing simulator. The investigation shows that intertrack interference cancellation decreases bit error rate. Moreover, to obtain bit error rate of 10-3 and SNR1124kfci of 14 dB, TWR can be increased to about two times track pitch for Gs of 15 nm. For obtaining SNR1124kfci of 14 dB, TWR should be 15 nm at σ/Dave of 5% or TWR should be 11 nm at σ/Dave of 10%. These results demonstrate that ITIC effectively decreases bit error rate and thus contributes to attaining areal recording density of 5.8 Tbit/in.2.