Ready for the Bazillion-Byte Drive?

Thinking about writing your memoirs – putting your life story down on paper for all eternity? Why not skip the repetitive strain injury and just capture your whole life on full-video, putting it all in a device the size of a sugar cube? It might not be as far off as you think.

Currie Munce, director of IBM’s Advanced HDD Technology Storage System Division, has one avowed goal: Build bigger storage. Recently Munce and his fellow Ph.Ds restored Big Blue’s lead in the disk space race with a new world record for areal (bit) density: 35.3 gigabits per square inch – roughly three times as dense as any drive shipping at press time.

During the 1990s, areal density doubled every 18 months, keeping pace with the transistor density gains predicted by Moore’s Law. But increasingly daunting technical challenges face those who would push the storage envelope further. “I think magnetic recording technology has another good 5 to 10 years” says Munce. “After that, we’ll see substantial difficulties with further advances at the pace people are accustomed to.”

From here on, a phenomenon called superparamagnetism threatens to make densely-packed bits unstable. Provided that new developments continue to thwart superparamagnetic corruption, scientists speculate that the theoretical limit for discrete bit recording is 10 terabits per square inch (1 terabit = 10 gigabit).

Approaching this limit will require new technologies. Two possible contenders are atomic force microscopy (AFM) and holographic storage.

AFM would use a spinning plastic disk, perhaps inside a wristwatch, and a tiny, 10-micron cantilever with a 40-angstrom tip (an angstrom represents the approximate radius of an atom) to write data. In theory, AFM will allow densities of 300 to 400 gigabits per square inch.

While AFM is still in the lab, holographic storage is closer to reality. According to Rusty Rosenberger, optical program manager for Imation, “We are targeting a 40MB-per-second transfer rate.” Future iterations of holographic systems should improve substantially.

The three-dimensional nature of holography makes it an appealing storage medium because “page” of data can be superimposed on a single volume – imagine transferring a whole page of text at once as opposed to reading each letter in sequence. Hans Coufal, manager of IBM’s New Directions in Science and Technology Research division, predicts that the fast access rates and transfer times of holographic storage will lead to improved network searches, video on demand, high-end servers, enterprise computing, and supercomputing.

Meanwhile, also-run technologies are thriving. Tape, first used for data storage in 1951 with the Univac I, has been revitalized by the corporate hunger for affordable archiving solutions. In the consumer arena, says Dataquest analyst Mary Craig, recordable CD-ROMs and DVDs will remain the dominant high-capacity removable storage media for the next decade. Despite their failure to match the areal density gains of hard disks, optical disks are cheap to produce, making them ideal for software distribution (until a mature digital rights management system facilitates online delivery). Finally, solid state options such as flash cards can’t yet match the pricing of hard disks at high capacities.

Further out, scientists salivate over the prospect of data manipulation and storage on an atomic level. Because consumer demand for capacity is lagging behind what technology can deliver, bringing new storage options to the masses will depend on seeing the need for more space.