Researchers from Fujitsu say they have developed technology that allows more than 100 gigabits (Gb) of data to be stored on one square inch of hard disk space — a new record that is expected to lead to notebook hard drives with capacities of over 100GB appearing on the market within the next year.

The technology, developed at the Fujitsu Laboratories outside Tokyo, allows 106Gb of data to be stored per square inch, significantly more than the 27.5Gb and 32.6Gb per square inch recently announced by Seagate and Toshiba respectively.

To achieve the higher recording density, Fujitsu developed a recording medium consisting of two magnetic layers separated by a thin layer of a nonmagnetic spacer material, in this case the element Ruthenium (Ru). The new design, called SF Media by Fujitsu, allows a recording density three times greater than has been possible until now, said Minoru Sekiguchi for Fujitsu.

To make use of the new medium, the company also had to develop a better disk drive head capable of writing and reading data in smaller spaces. The data playback level of the head was doubled through the use of a specular GMR (giant magnetoresistive) read head with two active layers (current disk drives have one active layer) and data recording ability was increased by 30 percent thanks to a higher-precision write head, said Sekiguchi.

At around 100Gb per square inch, the technology rivals the 'pixie dust' magnetic coating technology that IBM announced in May.

IBM said pixie dust will offer similar densities but is not predicting it will be available commercially until 2003.

Fujitsu, in contrast, said its new technology will begin appearing in commercial products in the first or second quarter of 2002 and that engineers, with the barrier of 100Gb per square inch broken, are now working towards the development of densities of around 300Gb per square inch. The company would not speculate as to when this might be possible.