Chris Evans points to an interesting "jet analogy" in his post[Your Data On a Knife Edge].To help people understand that significance of this innovation, IBM Research has a website with all kindsof useful GMR information: http://www.research.ibm.com/research/gmr.html
While many people associate GMR heads with disk drives, it also applies to tape.In 2006, IBM Researchers Set World Record in Magnetic Tape Data Density, recording 6.67 billion bits per square inch of tape media. This was achieved with specific developments:
- New high-density dual-coated particulate magnetic tape: Developed by Fuji Photo Film Co., Ltd., in Japan in collaboration with IBM Almaden researchers, this next-generation version of its NANOCUBIC™ tape uses a new barium-ferrite magnetic media that enables high-density data recording without using expensive metal sputtering or evaporation coating methods.
- More sensitive read-write head: For the first time, magnetic tape technology employs the sensitive giant-magnetoresistive (GMR) head materials and structures used to sense very small magnetic fields in hard disk drives.
- GMR servo reader: New GMR servo-reading elements, software and fast-and-precise positioning devices provides an active feedback system with unprecedented 0.35-micron accuracy in monitoring and positioning the read-write head over the 1.5-micron-wide residual data track.
- Improved tape-handling features: Flangeless, grooved rollers permit smoother high-speed passage of the tape, which also enhances the ability of the head to write and read high-density data.
- Innovative signal processing algorithms for the read data channel: An advanced read channel used new "noise-predictive, maximum-likelihood" (NPML) software developed at IBM's Zurich Research Laboratory to process the captured data faster and more accurately than would have been possible with existing methods.
IBM often leverages the research done in one part of its business over to other parts of its business. In this manner, advances in disk translate into advances in tape, keeping tape a viable medium for at least the next 8-10 years.