5 Gb/in(2) recording with dual stripe AMR heads and low noise thin film disks

We have demonstrated magnetic recording at an areal density of 5 Gb/in(2) u sing Dual Stripe Magnetoresistive heads (DSMR) on low noise and low-glide h eight quaternary CoCrTa-based alloy thin film disks. The data rate is 120 M b/sec with a PR4 channel, and the on-track error rate achieved is around 10 (.9). The demonstration was accomplished in two cases using two different t ypes of heads. In the first case, it was done with a DSMR head having shiel d-shield spacing of 0.165 mu m and 1 mu m stripe height flying at 25 nm, re sulting in a linear density of 321.7 KBPI, and a track density of 15.6 KTPI . The second case was performed with DSMR heads having shield-shield spacin g of 0.18 mu m and .8 mu m stripe height flying at proximity height of 12 n m, achieving a 358.75 KBPI and 13.8 KTPI. This is the highest linear densit y published so far for either GMR or AMR heads. It is the direct consequenc e of high signal/noise of DSMR heads and proximity recording over low noise , low-glide-height media. To explore the large dynamic range of DSMR heads, this study was also done with a variety of low noise disks with Mrt rangin g broadly from 0.45 to 1.0 memu/cm(2) and coercivity of 3000 Oe.