NIST Tech Beat - November 9, 2006

For the first time, tornado-like rotational motions have been transferred from light to atoms in a controlled way at the National Institute of Standards and Technology (NIST). The new quantum physics technique can be used to manipulate Bose-Einstein condensates (BECs), a state of matter of worldwide research interest, and possibly used in quantum information systems, an emerging computing and communications technology of potentially great power.

As reported in the Oct. 27 issue of Physical Review Letters,* the research team transferred orbital angular momentum—essentially the same motion as air molecules in a tornado or a planet revolving around a star—from laser light to sodium atoms.

The NIST experiment completes the scientific toolkit for complete control of the state of an atom, which now includes the internal, translational, and rotational behavior. The rotational motion of light previously has been used to rotate particles, but this new work marks the first time the motion has been transferred to atoms in discrete, measurable units, or quanta. Other researchers, as well as the NIST group, previously have transferred linear momentum and spin angular momentum (an internal magnetic state) from light to atoms.

The experiments were performed with more than a million sodium atoms confined in a magnetic trap. The atoms were chilled to near absolute zero and in identical quantum states, the condition known as a Bose-Einstein condensate in which they behave like a single “super-atom” with a jelly-like consistency. The BEC was illuminated from opposite sides by two laser beams, one of them with a rotating doughnut shape. Each atom absorbed one photon (the fundamental particle of light) from the doughnut laser beam and emitted one photon in the path of the other laser beam, picking up the difference in orbital angular momentum between the two photons. The interaction of the two opposing lasers created a corkscrew-like interference pattern, inducing the BEC to rotate—picture a rotating doughnut, or a vortex similar to a hurricane.

The researchers demonstrated control over the process by inducing the cloud of atoms to simultaneously rotate and stand still, or to rotate simultaneously in opposite directions with varying amounts of momentum—a mind-bending peculiarity of quantum physics known as superposition.

The research team included staff from NIST and the Joint Quantum Institute operated by NIST and the University of Maryland, as well as guest researchers from the Indian Institute of Science, Bangalore, India, and Institut für Experimentalphysik, Universität Wien, in Austria. The work was funded in part by the Office of Naval Research, the National Aeronautics and Space Administration, and the Advanced Research and Development Activity.

* M.F. Andersen, C. Ryu, P. Cladé, V. Natarajan, A. Vaziri, K. Helmerson, and W.D. Phillips. 2006. Quantized rotation of atoms from photons with orbital angular momentum. Physical Review Letters. Oct. 27.

Robots running amok and destroying property may be a staple in science fiction films, but they aren't welcome in factories, warehouses and other places where automatic guided vehicle (AGV) forklifts are used. Under a cooperative research and development agreement with Transbotics, a Charlotte, N.C., AGV manufacturer, the National Institute of Standards and Technology (NIST) is developing advanced sensor processing and modeling algorithms to help robot forklifts verify the location and orientation of pallets laden with goods.

The experimental system utilizes two onboard, single scan-line LADAR devices to negotiate obstacles and hone in on warehouse pallets. (LADAR—Laser Detection and Ranging—is an optical technology which measures properties of scattered laser light to find range and other information about a distant target.) One LADAR device, located at the base of the AGV, is used as a safety sensor to detect obstacles such as humans in the forklift's path. It also can be used to scan inside a truck's cargo area to detect the presence of a pallet or define distances from the forklift to the truck's inside walls.

The other sensor, called the Panner, is a panning laser ranger mounted on a rotating motor at the top front of the AGV. The Panner acquires many scan lines of range data that allows the scene in front of the device to be reconstructed in various visual formats such as a pseudo-colored coded image (where colors indicate relative proximity to an object) or a 3-dimensional data point “cloud.” A computer model is then derived from the data with the output sent immediately to the AGV's control center. This allows the robot forklift to maneuver, load and unload pallets, verify the remaining space within the truck being loaded, and track the number of pallets still needing handling.

The research team recently presented the results of its visualization program at the SPIE Optics East 2006 Conference in Boston.* Transbotics is planning to implement the NIST pallet verification software on one of its AGVs in 2007 for use in real manufacturing situations.

* R. Bostleman, T. Hong and T. Chang. Visualization of Pallets. Presented at the SPIE Optics East 2006 Conference. October 2006 (published online Oct. 2, 2006).

Researchers at the National Institute of Standards and Technology (NIST), Intelligent Automation, Inc. (Rockville, Md.) and the University of Missouri-Columbia have modified a NIST-designed microphone array to make an “audio telescope” that could help airports more efficiently avoid costly and hazardous bird-aircraft collisions by locating and identifying birds by their calls. The prototype system was described in a recent paper.*

From chirps to trills, bird song usually is soothing and restful—unless you're a pilot. Collisions with birds in flight, called “bird strikes,” caused over $2 billion worth of damage to aircraft in the United States or U.S. aircraft abroad, since 1990, according to statistics from the Federal Aviation Administration. Worldwide, wildlife strikes —mostly birds—have destroyed more than 163 aircraft and killed more than 194 people since 1988.

Airports fight back with X-band radar and infrared cameras to monitor birds, but neither technology can distinguish between different kinds of birds, particularly in bad weather. That's important because not all birds are equally hazardous to aircraft, and shutting down runways because of the proximity of unknown birds imposes its own costs in delays and increased aircraft congestion. The “audio telescope” proposed by NIST and IAI researchers is a one-meter-diameter concentric array of 192 microphones that would be mounted parallel to the ground to listen to the skies. By comparing the arrival time of sounds at different microphones, the array can determine the direction from which the sound came, even distinguishing simultaneous sounds coming from different directions. The researchers adapted mathematical algorithms designed to allow speech recognition systems to identify different speakers in order to distinguish different species by their calls. The system can tell a Canada goose from a gull or a hawk within a couple of seconds.

The acoustic bird monitor is an extension of the NIST Mark-III Microphone array, a high-performance, directional, audio signal processing system developed as a test platform for speech-recognition computing systems in complex sound environments, such as meeting rooms. Development of the prototype was funded by the Air Force Office of Scientific Research.

* C. Kwan, K.C. Ho, G. Mei, Y. Li, Z. Ren, R. Xu, Y. Zhang, D. Lao, M Stevenson, V. Stanford, C. Rochet. An automated acoustic system to monitor and classify birds. EURASIP Journal on Applied Signal Processing. Vol. 2006.

In industries from textiles to automobiles and from pharmaceuticals to semiconductors, accurately measuring empty spaces—technically speaking, porosity—is a substantial matter, important to efforts to ensure high product quality and low scrap rates.

This is because tiny pores—usually smaller than 50 nanometers in diameter—come in many varieties, creating complex internal and external surface features that strongly influence the performance of catalysts, filters, brake pads, pigments, ceramic components, time-release capsules and many other engineered products.

A new Recommended Practice Guide from the National Institute of Standards and Technology (NIST) provides useful advice and instruction on how to analyze the size, distribution and total volume of tiny pores. The 79-page manual, Porosity and Specific Surface Area Measurement for Solid Materials, was jointly produced by scientists from NIST and Germany's Federal Institute for Materials Research and Testing (BAM).

The two government research organizations are collaborating to produce certified reference materials. These reference materials are carefully characterized samples that serve as benchmarks for evaluating the accuracy of instruments used to measure the chemical composition or certain physical properties of materials. For example, NIST and BAM offer samples of alumina beads (NIST Standard Reference Material 1917) with certified values for pore volume, mean pore diameter, and most common pore diameter.

Industry uses a variety of methods to measure the surface area and pore characteristics of powders and other materials characterized by large surface-to-volume ratios. Differences among the methods complicate efforts to compare and interpret measurement results. Also, strengths and limitations of the various techniques are important for manufacturers to know when designing materials with pore sizes and distributions optimized for specific applications and products. The new guide details the “practical issues that need to be considered when conducting a measurement or analysis” by one or more of the commonly used porosimetry techniques.

To request a copy of Porosity and Specific Surface Area Measurement for Solid Materials, NIST Recommended Practice Guide, NIST SP 960-17, send an e-mail to denise.shaw@nist.gov.

Heads of federal agencies, chief information officers and any manager who needs a broad overview on information security practices will be interested in a new information security handbook recently issued by computer security experts at the National Institute of Standards and Technology. Information Security Handbook: A Guide for Managers (NIST Special Publication 800-100) is aimed specifically at helping managers at federal agencies better understand how to establish and implement an information security program. As the reliance by federal agencies on information technology has grown, so has the need to implement appropriate, cost-effective security controls. This comprehensive guide includes chapters on information security governance; security planning; designing, developing and implementing an awareness and training program; integrating IT security into the capital planning process; risk assessment and management; and incident response among other important security topics. Information Security Handbook: A Guide for Managers (SP 800-100) and other NIST information security publications are available at http://csrc.nist.gov/publications/nistpubs/index.html.

The National Institute of Standards and Technology (NIST) has posted at www.nist.gov/speech/tests/mt the results of the NIST 2006 Machine Translation Evaluation (MT-06), part of an ongoing series assessing the effectiveness of the technologies underlying computerized text language translation systems. NIST conducts these evaluations in order to support machine translation (MT) research and help advance the state of the art in MT technology.

MT-06 consisted of two tasks where each task required performing translation of text from a given source language into the target language. The source languages were Arabic and Chinese, and the target language was English. Research algorithms and translation system output—not the systems themselves—were studied in MT-06. These tests should not be considered a product-testing exercise and the results should not be used to make conclusions regarding which commercial products are best for a particular application.

MT-06 results are not to be construed or represented as endorsements of any participant's system or commercial product, or taken as official findings on the part of NIST or the U.S. government.

Steven M. Bellovin, a pioneer researcher on network security, will be presented with the 2007 National Information Systems Security Award by the National Institute of Standards and Technology (NIST) and the National Security Agency (NSA) in a ceremony during the 22nd Annual Computer Security Applications Conference (ACSAC) in Miami Beach, Fla., on Dec. 11-15, 2006.

Bellovin, currently a professor of computer science at Columbia University, was one of the originators of USENET as a graduate student at the University of North Carolina in the late 1970s. During more than 20 years of research at Bell Labs and AT&T Labs Research, Bellovin was one of the first researchers to recognize the importance of firewalls to network security, explore protocol failures, discuss routing security and utilize encrypted key exchange protocols. Bellovin has served on numerous National Research Council computer security committees, and is a member of the National Academy of Engineering and the Department of Homeland Security's Science and Technology Advisory Board. He is the co-author of Firewalls and Internet Security: Repelling the Wily Hacker, and holds several patents on cryptographic and network protocols.

The award recognizes individuals for scientific or technological breakthroughs, outstanding leadership, highly distinguished authorship or significant long-term contributions in the computer security field.

For more about Bellovin, go to his Web site at www.cs.columbia.edu/~smb. For information on past National Information Systems Security Award winners as well the upcoming ACSAC conference, see www.acsac.org.

Five senior members of the National Institute of Standards and Technology (NIST) staff have been honored in the 2006 Presidential Rank Awards. The awards recognize exceptional long-term accomplishments in public service by career senior government executives.

There are two categories of rank awards: Distinguished and Meritorious. This year's Distinguished category honorees include: Katharine B. Gebbie, Director of the NIST Physics Laboratory; W. Todd Grams, NIST Chief Financial Officer; and Robert J. Celotta, a NIST Fellow and leader of the Electron Physics Group. Honorees in the Meritorious category include: Robert F. Moore, Chief Facilities Management Officer; and James E. Faller, Senior Research Scientist in the Quantum Physics Division.

Award winners are nominated by their agency heads, evaluated by boards of private citizens, and approved by the President. The evaluation criteria focus on leadership and results. See www.opm.gov/ses/presrankaward.asp.

Physicist David J. Wineland of the National Institute of Standards and Technology's (NIST) Time and Frequency Division has been named to the 2006 list of the Scientific American 50, along with Christopher R. Monroe of the University of Michigan at Ann Arbor, for his research on quantum computing. The honors were announced in the magazine's December issue.

Wineland was recognized in particular for leading a research group that this year created a novel electromagnetic trap for ions that could be easily mass produced to potentially make quantum computers large enough for practical use. See: “New Ion Trap May Lead to Large Quantum Computers” www.nist.gov/public_affairs/techbeat/tb2006_0706.htm#ion.

The American Physical Society (APS) announced last week the selection of National Institute of Standards and Technology (NIST) physicist Jun Ye, to receive the 2007 I.I. Rabi Prize. Named for the 1944 Nobel Laureate Isidor Isaac Rabi, the award is made every two years by the APS “To recognize and encourage outstanding research in Atomic, Molecular and Optical Physics by investigators who have held a Ph.D. for 10 years or less.”

Ye, a NIST Fellow in the Quantum Physics Division also is a Fellow of JILA, a cooperative research institute of NIST and the University of Colorado at Boulder, and serves as a professor adjoint in the CU-Boulder physics department.

He is being recognized “for advances in precision measurement, including techniques for stabilizing and measuring optical frequencies, controlling the phase of femtosecond laser pulses, and measuring molecular transitions.”

Past winners of the prestigious award include his colleagues Deborah Jin and Eric Cornell. See www.aps.org/praw/07winners.cfm.

(Return to NIST News Page)

Editor: Michael Baum

Date created: November 9, 2006
Date updated: November 9, 2006
Contact: inquiries@nist.gov