Physicists Split Atoms to Improve Superconductors
A Mouse That Scrolls
Deep Blue Branches Out
Disk Drives Soar in Storage Capacity
Performance Gains for ThinkPad 770
Physicists Split Atoms to Improve Superconductors
In the decade since Georg Bednorz and Alex Müller of IBM's Zurich Research Laboratory received the Nobel Prize in physics for discovering high-temperature superconductivity in ceramic copper oxides, the phenomenon has caused much excitement but also much frustration. One problem stems from the fact that the relatively high temperatures facilitate the movement of magnetic field lines, produced by outside fields and the superconducting currents themselves, through wires and other devices made of these superconductors. That motion results in electrical resistance to the flow of current, rendering new compounds unstable as superconducting wires.
Physicists have known for some time how to solve the problem: insert defects in the superconductor to "pin" the magnetic field lines. Practically, though, that presents problems. "The field lines are 'soft,' like cooked spaghetti," says Lia Krusin-Elbaum, of the Thomas J. Watson Research Center. "When you anchor one end, the rest can still jiggle around." To prevent jiggling, it's necessary to create cylindrical traps just a few tens of Angstroms in diameter in the wires' crystal structure that will swallow up the magnetic field lines in their entirety and thus immobilize them.
How can such traps be created in superconducting wires without damaging the wires? One method is to bombard the wires with fast heavy ions, such as gold or lead, from the outside. However, such ions cannot penetrate deeply enough into thick wires to pin the field lines efficiently.
Krusin-Elbaum at Watson, leading an effort involving the Los Alamos, Oak Ridge and Argonne national laboratories and several universities, devised a daring two-stage approach. They decided to split heavy atomic nuclei inside the superconductors themselves. They reasoned that fragments of the nuclei, produced by firing high-energy protons at wires made up of superconducting cuprates, would create long tracks inside the wires that should absorb and anchor all magnetic field lines. Krusin-Elbaum and her collaborators first demonstrated the nuclear fission technique for bismuth - a heavy atom contained in one kind of high-temperature superconductor.
To attain large supercurrents at the highest possible temperatures, they decided the best candidate for splitting among nuclei in high-temperature cuprate superconductors was mercury. Last year, Krusin-Elbaum and scientific colleagues exposed samples of a mercury-based superconductor to a proton beam at the Los Alamos National Laboratory. The result, they report in the scientific journal Nature, "was the first experimental record of a mercury fission process" to create tracks inside superconducting wires. After the irradiation, they found that the material remained an effective superconductor above 100 degrees K in high magnetic fields. "This has solved the pinning problem," says Krusin-Elbaum. Moreover, the wires retain only minimal radioactivity; they can be safely handled after a relatively short time, which can be reduced still further by using a less energetic proton beam.
The improvement brought about by the internal atom-splitting, she adds, is mostly useful in applications that require wires and tapes made of superconducting material. Krusin-Elbaum and postgraduate students Daniel Lopez and Dian Petrov have since shown that the technique works for mercury cuprates with different atomic structures. And they believe that the process can be extended to the most structurally anisotropic mercury/copper oxides that superconduct at temperatures above 130 degrees K and that can be fabricated into wires and tapes.
A Mouse That Scrolls
IBM's Consumer Division has introduced the ScrollPoint(TM) Mouse, an innovation from the Almaden Research Center that enables users of personal computers to surf the Net and navigate through long documents and spreadsheets more easily than before. The new mouse is included in the S and 1
series of IBM's Aptiva® personal computers.
Eliminating the need for scroll bars, the device permits users to move up, down, left, right and diagonally with just the touch of a finger. It also has
a zoom control that enables the user to choose the best view of a document, an autoscroll that adjusts scrolling speed, and jumping features that
give easy access to commonly used
icons, bypassing menus and title bars.
Simpler scrolling may seem a somewhat modest achievement. But according to Ted Selker, an IBM Fellow at Almaden who led the team that produced the new device, even a 5 percent increase in navigational or surfing speed is judged as impressive by users. "We devoted a lot of effort to making a device that navigates with 30 percent more speed than any other mouse device we know of," says Selker.
Deep Blue Branches Out
Will Deep Blue® go from the chessboard to the big board? That's at least a possibility for the IBM computer that stunned the world by beating human world chess champion Garry Kasparov (see "Deep Blue Sweeps Through,"
Research, Number 2, 1997). The team at Thomas J. Watson Research Center that designed Deep Blue has announced that it will now spend most of its time on projects other than chess.
"We have told Garry that IBM will not sponsor a rematch with him in the foreseeable future," says C.J. Tan, who heads the Deep Blue team. "We're exploring several areas of activity." Those areas would use the ability of Deep Blue's technology, based on an IBM RS/6000(TM) SP®computer, to analyze hundreds of millions of moves - or other actions - per second.
One set of investigations involves data mining techniques. The group has done preliminary work and is studying its application to epidemiology and other areas of health care. "It's going to be long-term research," says Tan. "We're in the beginning stages." Other areas of investigation for Deep Blue include risk management and simulation of molecular dynamics.
The Watson team has not
given up chess entirely. Members recently returned from promotional tours of Asia and Europe, during which Deep Blue Jr.,
a downsized version of the chess computer, was introduced to the media and played against local humans. "Customers were very excited," says Tan, "and the RS/6000 SP is doing very well around the world. A lot of people are interested because of Deep Blue."
Individual chess players may soon have the opportunity to take on the machine. The Watson team is exploring the commercial possibilities of an online version. And while Tan's group has forgone another match with Kasparov, it does not intend to keep Deep Blue Sr. away from chess challenges permanently. However, says Tan, "we want to apply the knowledge we have gained from chess to other fields of research."
http://www.chess.ibm.com/home/html/b.html
Disk Drives Soar in Storage Capacity
Less than a decade after it was first discovered, the giant magnetoresistive (GMR) effect has found its way into a commercial product. In December, IBM started to ship disk drives based on GMR technology perfected at the company's Almaden Research Center and its Storage Systems Division.
The drives have 16.8 gigabytes of storage capacity - eight times as much as drives currently used for desktop personal computers. Each new drive can hold eight hours of full-motion video or information that, in printed form, would fill more than 16 pickup trucks. By the year 2001, IBM foresees the technology enabling drives with more than 10 billion bits per square inch of storage capacity.
French scientists discovered the GMR effect in 1988, using pure crystals and very high magnetic fields. The following year, Almaden researchers demonstrated the effect in multilayered polycrystalline samples, which are much easier to make. Two years later, they developed structures called spin valves, which responded to the much smaller magnetic fields produced by written
data in hard disk drives. Since then, Almaden and the storage division have collaborated to bring the technology to fruition in the new disk drives.
GMR's path from discovery to commercialization was much faster than that for magnetoresistive heads, the highest-capacity storage technique now available. The key:
cooperation among IBM divisions. "We've had extremely tight coupling between Research and development teams in the storage division," says Almaden director John Best. "We've been able to improve the technology and very rapidly introduce it
into products."
http://www.research.ibm.com/research/gmr.html
Performance Gains for ThinkPad 770
IBM recently released its "Extreme Performance" ThinkPad 770, the first notebook computer with a DVD-ROM drive that can play digital versatile disc (DVD) movies. It owes much of its new capability to work at three Research laboratories. Scientists at the Thomas J. Watson Research Center, helped by the Almaden Research Center, developed a demultiplexer, a device driver and descrambling software specifically for the 770. A contribution from the Haifa Research Laboratory led to high performance software - rather than hardware - audio decoding for DVD movies.
Watson's demultiplexer allows the user to change the audio and video streams dynamically, and to explore DVD's multilanguage and multiple-camera-angle capabilities. The device driver drives an MPEG-2 decoder card manufactured by the IBM Microelectronics Division. It also enables fast-forward/reverse playing of the discs. And the descrambling software "prevents hackers from looking in on the programs and copying the unscrambled DVD movies," says Watson's Wai-Man Lam. "It is the first software implementation of a DVD descrambling algorithm."
Starting in January 1997, Watson and Almaden worked on an accelerated schedule to customize its contributions. "The demultiplexer and device driver took about nine months, and the descrambler about six months," recalls Lam. The Haifa lab, meanwhile, had delivered its full software implementation of the Dolby® AC-3 decoding algorithm in July 1996. Dolby Labs, Inc., certified the software's adherence to its quality criteria four months later. "The decoder has been highly optimized both in the algorithmic aspect and specifically for the Pentium platform, achieving world-class performance," says Haifa's Dror Gill.
