NIST Tech Beat - May 7, 2004

System Sets Speed Record for Quantum Encryption

Physicist Joshua Bienfang sets up the NIST quantum key distribution system to receive a string of photons from colleagues stationed on the top floor of the NIST Administration Building (shown in the background.) The black instrument on the left is an 8-inch telescope used in collecting the incoming photons.

Photo by Gail Porter/NIST

The fastest known cryptographic system based on transmission of single photons—the smallest pulses of light—has been demonstrated by a team at the National Institute of Standards and Technology (NIST). The transmissions cannot be intercepted without detection, so that messages encrypted with the system can be kept secret.

The NIST “quantum key distribution” (QKD) system transmits a stream of individual photons to generate a verifiably secret key—a random series of digital bits, each representing 0 or 1, used to encrypt messages—at a rate of 1 million bits per second (bps). This rate is about 100 times faster than previously reported systems of this type.

The demonstration, described in the May 3 issue of Optics Express, is the first major reported result from a new NIST testbed built to demonstrate quantum communications technologies and cryptographic key distribution. The testbed provides a measurement and standards infrastructure for research, testing, calibrations and technology development. Scientists tested the QKD system by generating an encryption key that could be sent back and forth between two NIST buildings that are 730 meters apart. They are using the testbed to develop data-handling techniques associated with this type of encryption.

Acadia Optronics LLC of Rockville, Md., consulted on the system design and hardware. Partial funding for the project was provided by the Defense Advanced Research Projects Agency.

For further information, see www.nist.gov/public_affairs/releases/quantumkeys.htm.

Media Contact:
Laura Ost, (301) 975-4034

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Sea Turtle Health Linked to Contaminants

Jennifer Keller prepares to take a blood sample from a loggerhead sea turtle as part of her doctoral studies at Duke University. Keller is now a NIST post doctoral researcher.

Photo by Larisa Avens/NMFS

L oggerhead sea turtles may be getting sick because of environmental exposure to toxic organic chemicals, such as polychlorinated biphenyls (or PCBs) and pesticides, according to a new study led by Duke University, with collaboration from the National Institute of Standards and Technology (NIST), and other organizations.

Released on April 21 in the online edition of Environmental Health Perspectives, the study found that turtles with higher concentrations of contaminants had poorer health. The authors note that the correlations suggest, though do not prove, a cause-and-effect link.

The new study is the first to investigate sea turtle health effects linked to a class of chemicals called organochlorines that are known to sicken other wildlife. Scientists took blood and fat samples from 48 live juvenile turtles captured in North Carolina waters and carried out clinical health assessments. Duke then worked with NIST researchers to measure the samples for concentrations of 80 different PCB and pesticide compounds. The research team found significant correlations for a wide variety of biological functions, suggesting, for example, changes in the immune system, possible liver damage, and possible alterations in protein and carbohydrate regulation.

The data may help scientists understand and address population declines in sea turtles, all species of which are threatened or endangered.

The NIST work was performed at the Hollings Marine Laboratory in Charleston, S.C., in which NIST is a partner. Researchers from the New England Aquarium and North Carolina State University also collaborated on the sea turtle research. Funding was provided by the Morris Animal Foundation, Disney Wildlife Conservation Fund, Oak Foundation, and Duke University Marine Biomedical Center.

Media Contact:
Laura Ost, (301) 975-4034

Uncertainty in Clinical Tests Raises Health Care Costs

Small measurement uncertainties in clinical laboratory tests can add large amounts to health care costs, according to a newly released study commissioned by the National Institute of Standards and Technology (NIST).

The study,* conducted by RTI International (Research Triangle Park, N.C.) and the Mayo Clinic (Rochester, Minn.), estimates that calibration errors in measurements of calcium levels in blood may add between $60 million and $199 million to U.S. health care costs annually. High calcium levels can be a symptom of diseases such as cancer and thyroid disorders.

Accurate measurements are critical because calcium levels in healthy people fall within a narrow range, between 8.9 to 10.1 milligrams (mg) per deciliter (dL). Through interviews with laboratory managers and equipment manufacturers, the researchers estimated that results for up to 15 percent of calcium laboratory tests contain calibration errors of between 0.1 and 0.5 mg per dL. This means that some results that fall in the center of the "normal" range, say 9.7 mg/dL, may in fact be for patient samples with elevated calcium, defined as 10.2 mg/dL and above. At the same time, patients with measured values above the threshold, but who actually have normal calcium levels, may receive unnecessary follow-up procedures such as hormone measurements and chest X-rays.

The study analyzed data for more than 89,000 patients receiving serum calcium tests at the Mayo Clinic from 1998 to 1999. It found that calibration errors added between $8 and $89 per patient to the health care costs of approximately 3.55 million patients.

Major sources of calibration error include differences in analysis methods used by different laboratory instruments, lot-to-lot variations in calibration materials, and lack of "traceability" between secondary reference materials and primary standards such as Standard Reference Materials produced by NIST.

Full text of the report is available at http://www.nist.gov/director/prog-ofc/report04-1.pdf (.pdf; download Acrobat Reader).

Media Contact:
Laura Ost, (301) 975-4034

* The Impact of Calibration Error in Medical Decision Making, printed copies available by contacting Denise Herbert,
(301) 975-2667, denise.herbert@nist.gov.

Superconducting R&D Wire Achieves Major Milestone

Using improved processing equipment developed with support from the National Institute of Standards and Technology's Advanced Technology Program, American Superconductor Corporation (AMSC) has produced lengths of record-breaking high-temperature superconductor (HTS) wire.

The company recently announced that it achieved electric current carrying capacity in multiple 10-meter lengths of second-generation (2G) HTS wire equal to or better than 250 Amperes per centimeter of width, an industrial world record that approaches performance levels required for commercial applications. The company’s 2G results were achieved through a reel-to-reel liquid deposition production process that has been designed to be scalable to high-volume, low-cost manufacturing.

Large-scale use of 2G HTS wire carrying high amperage electrical current with virtually no resistance promises dramatic gains in energy efficiency. Today about 10 percent of transmitted electricity is wasted, largely due to resistance. The new technology also can increase the efficiency of large electric motors by as much as 50 percent and enable smaller, more powerful magnetic resonance imaging machines for medicine.

The 2G wires will cost less than first-generation HTS wire. AMSC received ATP support to develop a large-scale continuous-process reaction furnace for producing 100-meter lengths of 2G HTS ribbon, a key element for practical commercial production of the wire.

More information on the AMSC 2G HTS wire project and a white paper on the technology may be found on the company’s Web site: www.amsuper.com.

Media Contact:
Michael Baum, (301) 975-2763

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Software Corrects Chip Errors Early

M icrochip miniaturization is making quality control-related measurement of features during the production process increasingly difficult. New National Institute of Standards and Technology (NIST) software and research results* should help manufacturers reduce errors in measuring microchip features which today measure less than 37 nanometers (about 1.5 millionths of an inch) in width and are expected to shrink to 25 nanometers (about 1 millionth of an inch) by 2007.
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Currently, most semiconductor manufacturers use scanning electron microscopes (SEMs) to measure circuitry lines when the chip is first being patterned. Circuit dimensions are formed when ultraviolet light is shined on a thin film of polymer laid over silicon. Exposed areas harden, allowing unexposed areas to be chemically etched into tiny troughs for laying down circuit lines. Errors caught before etching may be correctable, while those caught later may result in scrapping the wafer and loss of a sizeable investment.

The NIST software equips the SEMs with a “model library” of possible line measurements. Technicians can use the enhanced SEMs to match measured images with library images in order to more accurately determine the shapes and sizes of features. Using the new software can cut measurement errors from tens of nanometers down to a few nanometers. The new method also is more reliable. There is about three times less variation among repeated measurements of the same circuit feature using the software than with the current most commonly used method.

NIST and International SEMATECH, a consortium of leading semiconductor manufacturers that represent about half the world's semiconductor production, funded the “model library” work.

Media Contact:
John Blair, (301) 975-4261

* J.S. Villarrubia, A.E. Vladár, B.D. Bunday, and M. Bishop, “Dimensional Metrology of Resist Lines Using a SEM Model-Based Library Approach," Proc. SPIE 5375, expected publication summer 2004.

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MEP Named as Finalist in Government Award

The Manufacturing Extension Partnership (MEP) has been named as one of 15 finalists for the Innovations in American Government Award.

MEP is a nationwide network of resources managed by the U.S. Commerce Department’s National Institute of Standards and Technology for helping small manufacturers become more competitive.

On Jan. 16, 2004, Commerce Secretary Evans released a comprehensive manufacturing strategy, Manufacturing in America. A key part of that strategy includes continued support for the MEP and steps to review and improve its efficiency. Steps include teaming with the International Trade Administration and holding a recompetition for MEP centers. (For more information, see http://www.manufacturing.gov.)

MEP was one of nearly 1,000 applicants for the award. Five winners will be announced on July 28, 2004 at the Excellence in Government 2004 Conference, in Washington, DC. Each winning program will receive a $100,000 grant to encourage replication of its innovation in other jurisdictions. For more information on the Innovations in American Government Award, see http://www.excelgov.org.

Media Contact:
Jan Kosko, (301) 975-2767

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Two NIST Researchers Earn Presidential Honors

President Bush has named two researchers at the National Institute of Standards and Technology's Boulder, Colo., laboratories as recipients of the Presidential Early Career Awards for Scientists and Engineers (PECASE), the highest honor bestowed by the U.S. government on young professionals at the outset of their independent research careers. Jun Ye, of the Quantum Physics Division of NIST's Physics Laboratory, and Sae Woo Nam, of the Quantum Electrical Metrology Division of NIST's Electronics and Electrical Engineering Laboratory, were among 57 U.S. researchers chosen for the 2002 PECASE award. (Recipients of the 2003 awards will be named later this year.)

Both scientists will receive research grants to fund up to five years of research to further their studies in support of critical government missions.

For more information, go to http://www.ostp.gov/html/PECASErelease5-4-04.pdf. (.pdf; download Acrobat Reader).

(Editor's note: High-resolution color photos of Jun Ye and Sae Woo Nam are available from Gail Porter, (301) 975-3392, gail.porter@nist.gov.)

NIST/Chemical Safety Board Sign Agreement

The National Institute of Standards and Technology (NIST) signed a Memorandum of Understanding with the U.S. Chemical Safety and Hazard Investigations Board (CSB) on April 30 designed to increase cooperative efforts between the two agencies in protecting the public from accidents involving the release of hazardous chemicals. The agreement provides a mechanism for NIST and CSB to quickly share technical expertise, data, advice and investigative findings. Under the National Construction Safety Team Act, NIST is authorized to establish investigative teams to assess building performance and emergency response and evacuation procedures in the wake of any building failure that results in substantial loss of life or poses the potential for substantial loss of life. The full text of the MOU is available at: www.nist.gov/public_affairs/releases/csbmou.htm.

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Editor: Gail Porter

Date created: 05/076/04
Date updated:05/07/04
Contact: inquiries@nist.gov