Shape changing approach to data storage

Tom Shelley reports on two technologies set to revolutionise the storage and retrieval of computer data

Two emerging technologies could revolutionise the storage and retrieval of data. The first, an optical technology, is expected to allow data transfer, to and from disk, at 1Gbit/s by 2004. The second, a nano-scale, shape memory alloy technology, is likely to raise this figure to 200Gbit/s not too long afterwards. Information storage and retrieval is perceived, in certain circumstances, as a bottle neck in many systems, as it has not experienced advances commensurate with those experienced by processors and memory. Therefore, the ability to store and retrieve ever-increasing amounts of data quickly has lead to world-wide research into the many possible ways of overcoming this bottleneck. Cambridge-based Polight Technology is putting its efforts into Holinides, a class of materials initially developed at the University of Cambridge's Chemistry Department. As their name suggests, the technique is based on writing 1,000 x 1,000 pixel holograms into special glass, deposited on a 0.5mm thick disk, with each flash of a laser. They are read in a similar manner. The high data capacity and transfer rate arise because of the 3D data storage approach. The first commercial products will be non re-writable although re-writable products are expected to follow. The company's web site ( talks of read/write speeds of 6Gbit/s and storage of 10Tbit on a 120mm disk, although Eureka has been advised that commercial products expected to become available in 2004 are likely to be limited to 1Gbit/s and 1Tbit. Dr Tony Anson, a researcher at Anson Medical, a company spun out of the Brunel University, has another approach – a technique which he believes will allow data transfer rates of 200Gbit/s. His approach uses a single crystal layer of nickel-titanium, shape memory alloy, 10 to 20nm thick. When briefly heated by a 2nm diameter electron beam, very small dot areas change their shape through transformation from body-centred cubic crystalline structures to orthorhombic. The pattern of changed and unchanged dots can then be read by a lower-power beam. Warming up the whole or part of the thin film allows all dots to 'remember' their original shapes – erasing the data ready for re-writing. As far as we understand, the only substantial offer he has had to date appears aimed at temporarily suppressing the technology. Such an approach has never worked in the past in the IT industry, so we can look forward to even more massive data rates in the not too distant future. More information by e-mail from Dr Tony Anson and technology brokers JRA Technology. Pointers Optical based write-once-read-many technology looks likely to allow storage of 1Tbit of data with data read/write rates of 1Gbit/s by 2004. This will be followed by planned increases to 10Tbit and 6Gbit/s and the development of re-writable disks Nano scale dot technology written, read and erased by electron beams has the potential to permit data transfer rates of 200Gbit/s