201 Gb/in² Recording Areal Density on Sputtered Magnetic Tape

Abstract

A prototype perpendicularly oriented sputtered tape sample was investigated using a prototype high-moment tape write head and a 48 nm-wide tunneling magnetoresistive hard disk drive read head. A linear density of 818 kbpi with a post-detection byte-error rate <0.023 was demonstrated based on measured recording data and a software read channel that used an extended version of the noise-predictive maximum-likelihood detection scheme that tracks the mean of the data-dependent noise. Using a previously reported iterative decoding architecture, a user bit-error rate of <1e-20 can be achieved at this operating point. Track-following servo performance characterized by the standard deviation of the position error signal ( \sigma -PES) ≤ 6.5 nm was also demonstrated over a tape speed range of 1.2-4.1 m/s. This magnitude of PES in combination with a 48 nm-wide reader enables reliable recording at a track width of 103 nm corresponding to a track density of 246.2 ktpi, for an equivalent areal density of 201.4 Gb/in2.