Counting on the Small Scale
LabNotes
Finding Lost Light
Auto Loans
Made Easier
Honors - External Awards Go to
IBM Researchers
Storage
Under Glass?
How Perceptions Form in the Brain
Counting on the Small Scale
A research team at IBM's Zurich Research Laboratory has built the world's smallest abacus. The molecular-scale calculator uses the ultrafine tip of a scanning tunneling microscope (STM) to move and thereby count with "beads," each of which is an individual molecule. Extension of the work that led to the abacus could open up new methods of making useful devices in the so-called nanometer range.
To create the abacus, the Zurich team formed stable rows of 10 carbon-60 molecules, known as buckminsterfullerenes or "buckyballs," along steps just one atom high on a copper surface. These steps act as "rails" along which the molecules are moved. The steps resemble the grooves that kept the beads in line in the earliest abacuses. The STM tip pushes individual molecules back and forth to carry out a "calculation," whose result is then imaged when the STM scans the entire surface containing the buckyball beads.
"We have made significant progress in handling objects and creating functional units on the nanometer scale at room temperature," says James K. Gimzewski, leader of the Zurich laboratory's nanoscience project. "We may be able to assemble more complex structures from the bottom up, molecule by molecule, and thus break ground for entirely new fabrication technologies with a broad range of applications."
The effort, reported in Applied Physics Letters, is part of the PRONANO (processing on the nanometer scale) project. Sponsored by the Swiss Federal Office of Education and Science, this is part of the European Union's Strategic Program for Research in Information Technology.
Lab Notes
RESEARCH HOME PAGE
A recently redesigned Research external home page, containing details of ongoing and completed projects, can be found at http://www.research.ibm.com.
SPEECH RECOGNITION ENGINE
IBM has announced Simply Speaking, a speech recognition product that extends the company's VoiceType® technology. Scientists at the Thomas J. Watson Research Center contributed the speech recognition engine technology, took part in product planning and design, designed and implemented the toolkit and APIs, and will provide third-level product support. In a related development, Aptiva(TM) personal computers sold in Japan now incorporate VoiceType technology for Japanese dictation jointly developed by the Tokyo Research Laboratory, IBM's Advanced OS and Extension Group in Yamato, Japan, and the company's U.S.-based Speech Business Unit.
ELECTROMAGNETIC ANALYSIS TOOL
At the request of the IBM S/390® Division, Watson researchers have helped to develop the world's most powerful simulation tool to carry out full electromagnetic analysis of interconnections between chips in high-frequency processors.
TECHEXPLORER ON ALPHAWORKS
The TechExplorer plug-in for Windows 95 and NT, which provides hypertext and multimedia support, pop-up menus, hierarchical documents and other features for electronic publishing, has been featured on the IBM alphaWorks site. Designed by Research, it is available as a stand-alone tool or a Netscape plug-in.
Finding Lost Light
In 1920, astronomers first observed that light from bright, young stars detected on Earth is less intense than expected in certain regions of the spectrum. For 60 years, they have known that the lost-light spectrum - known as diffuse interstellar bands, or DIBs - stems from light absorption by some interstellar material. But what material? That's been a mystery.
Now, two scientists at IBM's Thomas J. Watson Research Center have strong evidence that the material is hydrogen, the most common element in the universe. Generations of astronomers have failed to identify the culprit, say IBM Fellow Peter Sorokin and senior scientist James Glownia, because the hydrogen absorbs the light in a highly unusual way.
Sorokin and Glownia theorize that two effects cause the DIBs: efficient scattering of light similar to the process that makes the Earth's sky appear blue, and complex interactions related to those that make lasers possible. The combination of the two processes allows the hydrogen found in clouds near bright stars to absorb visible light from the stars at frequencies that exactly match spots in the DIBs pattern, they state. Using their model, they have already assigned more than 70 of the 130 sharp DIBs to transitions in hydrogen molecules that exactly match astronomers' observations.
The Watson scientists, both experts in the operation of lasers, have
published their theory in the December 20 issue of The Astrophysical Journal. That puts the evidence squarely in the court of scientific opinion.
Auto Loans
Made Easier
As many a disgruntled customer knows, you can't
drive your dream car out of the showroom as soon as you agree on the price. Obtaining approval for an auto loan and completing the necessary paperwork can take several days, during which time the customer can only wait.
That's about to change. The Auto Loan Exchange (ALEX) developed by IBM Research cuts the waiting time for auto loan approvals to literally minutes. After six months of
pilot studies in the New York area, Research and IBM's Banking, Finance and Securities Group have made ALEX available to car dealerships throughout the U.S. More than 100 will install the system by year's end. Banks and finance companies enrolled in the ALEX network include Chase Manhattan, Nationsbank, Citibank and GE Capital.
To apply for a loan through ALEX, customers will enter data in an IBM workstation at the auto dealership. The system identifies errors in the credit application, customizes it, encrypts it and forwards it to auto finance companies and credit bureaus on the Internet, via high-speed leased lines belonging to the IBM Global Network. The customer's finance company reviews the application and responds immediately, via the same channel.
In the pilot installations, the complete process of application and approval has taken as little as five minutes. Research is now developing enhancements that will process insurance, registration, title and even vanity license plates, permitting the customer to drive away in the new car immediately.
The system stems from work at the Thomas J. Watson Research Center's Interactive Transactions Systems.The group remains a full partner in the enterprise. "We're working with the finance ISU to build up installation and maintenance teams," says Watson graphic designer Lauretta Jones, who oversees the effort. "I think it's going to catch on pretty quickly."
Honors - External Awards Go to
IBM Researchers
Jerry D. Tersoff of the Thomas J. Watson Research Center has garnered a rare double in awards from professional societies. He has recently received the 1996 Materials Research Society Medal for his contributions to the theory of strain relaxation in thin films. Tersoff showed that strain-induced roughening of thin films in semiconductors, which limits their applications, is thermally activated. Early in 1997, the American Physical Society will present him with its 1997 Davisson-Germer Prize in Atomic or Surface Physics. He won this award for his descriptions of surface phenomenology, notably involving crystal growth dynamics, surface structures and probes of the same.
The American Association for the Advancement of Science has elected Watson's Phaedon Avouris a Fellow. The fellowship marks his pioneering contributions to the chemistry and physics of metal and semiconductor surfaces, atom-resolved surface chemistry and atomic-scale lithography.
The Chinese American Academic and Professional Society (CAAPS) has presented its 1996 Academic Achievement Award to Watson physicist Chang C. Tsuei. The award acknowledges Tsuei's outstanding work in the observation of half-integer flux quanta in tricrystal cuprite superconductors.
The International Organization for Quantum Communication and Measurement has presented the 1996 Quantum Communications Award to Charles H. Bennett of Watson. The award recognizes his contribution to the foundation of quantum computing and cryptography.
Watson physicist Donald H. Weingarten has garnered the American Physical Society's 1997 Aneesur Rahman Prize, "for his seminal work on lattice chromodynamics including algorithmic innovations, massively parallel computer software development and hard- ware implementation." The work led to the identification of the glueball, the first time
an elementary particle has been identified by computation.
Christopher B. Murray of Watson has recently won the American Chemical Society's Nobel laureate Signature Award for Graduate
Education in Chemistry. The award recognizes his Ph. D. thesis on the synthesis and characterization of II-VI quantum dots
and their assembly into three-
dimensional quantum superdot lattices.
Storage
Under Glass?
One of the hurdles of holographic storage is the limitations of the materials used to store the holograms. Scientists at the Almaden Research Center have created a new family of glasses that overcome some of the difficulties.
In principle, data can be stored holographically when one of the two laser beams that create a hologram passes through a small cell containing a liquid crystal with transparent and opaque areas. The beam is then focused onto a photorefractive (PR) material, whose refractive index changes in response to light. Beams that have passed through transparent areas in the cell alter the PR material's refractive index more than those that have traveled through opaque regions. Areas with the two different indexes correspond to 0s and 1s in binary code. For retrieval, a single laser
beam creates images of the areas at a detector.
Almaden scientists discovered polymeric PR materials five years ago, but efforts to use them for holographic storage foundered owing to their instability and the expense of manufacturing them. The team realized that, in certain circumstances, some polymeric PR materials could take the form of glasses, which should last longer and be easier to manufacture. The team created a family of such glasses, known as
dihydropyridines, and tested their suitability for data storage. Not only are they longer-lived than other PR polymers, the group reported in Science; they also have higher storage capacity, by a factor of 10 to 100.
If holographic storage becomes commercially feasible, says team leader Donald Burland, the new materials could find use in second-generation forms of such storage. With continued refinement of the materials, he adds, the glasses could become commercially feasible in four to five years.
How Perceptions Form in the Brain
How does the brain combine the separate perceptual features of an object into a single, coherent perception? Scientists generally agree that the process involves binding together activity that occurs in separate, but interacting, groups of cells. Activity in one group may represent the brain's response to an object's color, while that in others would be associated with shape, texture, and so on.
One popular suggestion is that so-called gamma oscillations, known to
occur over large areas of the brain, bind together the activity in the various groups. What scientists have not understood until now is how these oscillations are synchronized across the groups. If one thinks of the individual groups as light bulbs blinking on and off, the problem is to understand how all blink at practically the same time. It is a problem because the synchronization is established much faster than the time signals take to travel across all the cell groups.
In a paper in the October 17 issue of Nature, Roger Traub, a scientist at the Thomas J. Watson Research Center, and three British collaborators propose a local mechanism to explain the coherence. Traub's computer simulations - confirmed by his collaborators' experiments on brain slices - have revealed that, in certain circumstances, pairs of so-called inhibitory neurons in the individual cell groups fire in rapid succession. These "spike doublets" cause the so-called excitatory cells in the group to undergo synchronized gamma oscillations.
It turns out, moreover, that the time between the two spikes roughly matches the period that a signal takes to travel from one group to another. The pair-wise interactions, therefore, are sufficient to induce a large-scale synchronization. Now, the team is following up this work in hopes of gaining a deeper understanding of how the brain perceives what the eyes see.
