Quantum Corp is predicting that by the year 2000, using Giant Magnetoresistive heads, it will be able to produce disk drives where individual 3.5 platters have 22Gb capacity. A magnetoresistive reading sensor is made of several thin layers of a magnetic material that changes its resistance in a magnetic field. The Giant Magnetoresistive effect was discoverd less than six years ago in France, in perfect-crystal samples exposed to very high magnetic fields – 20,000 Oersted, 40,000 times the earth’s magnetic field, 1,000 times than that used in disk drives. An IBM Corp scientist showed that more-easily-made sputtered polycrystalline multilayers even thinner than the layers in today’s magneto-resistive heads, also showed the Effect, and perfected it in its spin-valve design (CI No 2,437). Quantum says acquisition of Rocky Mountain Magnetics Inc will enable it to gain a lead on its competitiors, which it views as IBM Corp and Seagate Technology Inc. Other technologies it says it is working on include refinement of the Fibre Channel interface, glass platters to enable higher areal density, oil bearing spindles to increase the spin speed and provide better acoustics, the integration of RISC processors into its drives, and improved error correction.
