NIST TechBeat Blue/Yellow Banner NIST logo--go to NIST home page Search NIST web space go to NIST home page go to A-Z subject index Contact NIST skip navigation

January 30, 2004

  In This Issue:
bullet New Form of Matter Created: A Fermionic Condensate
bullet New Cryogenic Refrigerator Dips Chips into a Deep Freeze
bullet ‘Kissing’ RNA and HIV-1: Unraveling the Details
bullet Stirring Research Provides Recipe for Nanotube Success
bullet NIST Neutron Researcher Wins Inaugural Society Award
bullet Quick Links

[NIST Tech Beat Search] [Credits] [NIST Tech Beat Archives] [Media Contacts] [Subscription Information]

blue divider

New Form of Matter Created: A Fermionic Condensate

color image of condensate

image credit: NIST/University of Colorado

False color images of a condensate formed from pairs of fermion potassium atoms. Higher areas indicate a greater density of atoms.

Scientists at JILA, a joint laboratory of the National Institute of Standards and Technology (NIST) and the University of Colorado at Boulder (CU-Boulder) report the first observation of a “fermionic condensate” formed from pairs of atoms in a gas, a long-sought, novel form of matter. Physicists hope that further research with such condensates eventually will help unlock the mysteries of high-temperature superconductivity, a phenomenon with the potential to improve energy efficiency dramatically across a broad range of applications.

The research is described in a paper published in the Jan. 24-30 online edition of Physical Review Letters by JILA authors Deborah S. Jin, a physicist at NIST and an adjoint associate professor at CU-Boulder, and Markus Greiner and Cindy Regal, a post-doctoral researcher and graduate student at CU-Boulder.

The new work complements a previous major achievement, creation of a “Bose-Einstein” condensate, which earned JILA scientists Eric Cornell and Carl Wieman the Nobel Prize in Physics in 2001. Bose-Einstein condensates are collections of thousands of ultracold “boson” atoms occupying a single quantum state, that is, all the atoms are behaving identically like a single, huge superatom.

The new condensate is made with a different type of particle, fermions, that are inherently difficult to coax into a uniform quantum state.

Superconductivity, in which currents flow without resistance or losses, involves the pairing of electrons, which are also fermions. Quantum physicists are in worldwide race to produce fermionic condensates from gases because they are expected to exhibit a similar “superfluidity” similar to that seen in superconductors, but will be much easier to study.

“The strength of pairing in our fermionic condensate, adjusted for mass and density,” Jin explains, “would correspond to a room temperature super-conductor. This makes me optimistic that the fundamental physics we learn through fermionic condensates will eventually help others design more practical superconducting materials.”

For further details, see

Media Contact:
Gail Porter, (301) 975-3392



blue divider

New Cryogenic Refrigerator Dips Chips into a Deep Freeze

In a major advance for cryogenics, researchers at the National Institute of Standards and Technology (NIST) have developed a compact, solid-state refrigerator capable of reaching temperatures as low as 100 milliKelvin. The refrigerator works by removing hot electrons in a manner similar to an evaporative air-conditioner or “swamp cooler.”

When combined with an X-ray sensor, also being developed at NIST, the instrument will be useful in semiconductor manufacturing for identifying trace contaminants and in the astronomical community for X-ray telescopes. The device can be made in a wide range of sizes and shapes, as well as readily integrated with other cryogenic devices ranging in size from nano-meters to millimeters.

A report of the work is featured on the cover of the January 26, 2004, issue of Applied Physics Letters. “The idea is to use a solid-state refrigerator for on-chip cooling of these cryogenic sensors,” says Anna M. Clark, the report’s lead author. “We have a working refrigerator that reduces temperatures low enough to be used with highly sensitive X-ray detectors. These detectors require subKelvin temperatures to minimize thermal noise and maximize their resolution.”

Current equipment capable of cooling to 100 milliKelvin is bulky and expensive. By combining an on-chip cooler with an X-ray sensor, the NIST device may reduce substantially the weight and cost of such equipment.

The refrigerator is made from a sandwich of nomal- metal/insulator/superconductor junctions. When a voltage is applied across the “sandwich,” high-energy (hot) electrons tunnel from the normal metal through the insulator and into the superconductor. As the hottest electrons leave, the temperature of the normal metal drops dramatically.

Media Contact:
Gail Porter, (301) 975-3392


blue divider

‘Kissing’ RNA and HIV-1: Unraveling the Details

A subtle structural change that may play a role in the molecular machinery for making HIV-1 (the virus that causes AIDS) has been identified by scientists from the National Institute of Standards and Technology (NIST) and University of Maryland working at the Center for Advanced Research in Biotechnology (CARB). If confirmed in living cells, the mechanism, described in the Jan. 20 online edition of Proceedings of the National Academy of Sciences, might provide a new target for antiviral drugs.

John Marino working with nuclear magnetic resonance intrument
NIST research chemist John Marino places a RNA sample into the magnet of a nuclear magnetic resonance instrument.

The finding is among several to emerge recently from CARB’s efforts to develop and validate sensitive tools for rapidly detecting and quantifying ribonucleic acid (RNA) interactions. RNA provides the genetic blueprint for retroviruses such as HIV-1. CARB scientists created a model system for tracking changes in an RNA struc-tural element involved in forming HIV-1 viral particles.

As new HIV-1 viruses form and mature into infectious particles, two strands of RNA interact through a transient structure called a “molecular kiss.” This structure then is packaged into new virus particles, which undergo further maturation after release from the infected cell. CARB scientists found that specific sites in the “kissing” structure acquire a proton (a positively charged particle) at a pH close to that of living cells. The proton’s presence alters the RNA structure and accelerates its refolding by a protein associated with viral maturation. Taken together, these observations suggest that such a mechanism might be at work during viral infection.

To track RNA binding and folding in real-time, the CARB scientists developed fluorescent markers as substitutes for pieces of the RNA. By monitoring changes in the fluorescent signal, the scientists could follow these reactions. The scientists also used nuclear magnetic resonance to identify the sites in the RNA that acquire the proton and to characterize the resulting conformational changes.

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


blue divider

Stirring Research Provides Recipe for Nanotube Success

If manufacturing is entering the “Golden Age” of nanotechnology, then carbon nanotubes are the “Golden Child.” In recent years, these tubes of graphite many times thinner than a human hair have become a much-touted emerging technology because of their potential ability to add strength and other important properties to materials.

Adding carbon nanotubes to plastics and other polymers has potential to make automobile and airplane bodies stronger and lighter, and textiles more tear-resistant. And because of their electrical properties, carbon nanotubes also may be used to embed sensors in clothing for military and medical applications. By one estimate, the carbon nanotube market valued at approximately $12 million in 2002 could grow to $700 million by 2005.

One problem, however, is the nanotubes tend to clump together in certain applications. Just as an oil and water salad dressing must be shaken thoroughly to mix well, carbon nanotube formulations must be thoroughly blended to perform their best.

In a set of experiments reported in the Jan. 30 issue of Physical Review Letters, researchers at the National Institute of Standards and Technology (NIST) have started to quantify both the problem and the solution. The scientists used a microscope and an “optical flow cell” to measure the force needed to mix different concentrations of nanotubes. Their findings suggest that flow conditions often encountered in the processing of carbon nanotube suspensions can actually have the opposite effect, leading to demixing. The effect is related directly to the long fiber-like structure of the nanotubes. Although this work only sets the stage for resolving what will be an important technological issue, the findings give researchers insight into how to process nanotubes more efficiently.

Media Contact:
Scott Nance, (301) 975-5226



blue divider

NIST Neutron Researcher Wins Inaugural Society Award

J. Michael Rowe, director of the National Institute of Standards and Technology’s Center for Neutron Research (NCNR), will receive the first-ever Clifford G. Shull Award from the Neutron Scattering Society of America (NSSA). Established in 2002 in memory of the Nobel Prize winner of the same name, the award honors those who have made outstanding contributions to the field of neutron science.

In addition to his influential scientific work, NSSA officials said they selected Rowe to receive the inaugural award for being “a leader in the design of the latest generation cold neutron sources, including the most efficient hydrogen cold source currently operating in the world at the NCNR” and for providing leadership over 15 years as head of the NCNR that made the center the “most important and widely used neutron facility thus far developed in the United States.”

More than 1,900 participants from academia, industry and government conducted research last year that used neutrons at the NCNR to probe the structure and dynamics of materials.

Rowe plans to retire this year after a 31-year career at NIST.

NSSA represents more than 1,000 professionals in 26 nations. NSSA intends to present Rowe with the award at its biennial conference in June.

The Shull award consists of a plaque and a $5,000 honorarium.

Media Contact:
Scott Nance, (301) 975-5226


blue divider

Quick Links

Materials Practice Guide—The National Institute of Standards and Technology (NIST) has published a new practice guide, titled Data Evaluation Theory and Practice for Materials Properties, that provides guidance on how to assess data for reliability and consistency. The new guide represents NIST’s first formalized methodology for the evaluation of materials properties data. Industry will be able to use this publication to improve efficiency by ensuring that manufacturing processes are based on the best available data. The guide is available online at:

Nanotechnology workshop—The National Institute of Standards and Technology (NIST) hosted more than 200 representatives of government, academia and industry Jan. 27-29 for a “Grand Challenge” workshop aimed at developing the equivalent of a roadmap for metrology and instrumentation to further develop the emerging field of nanotechnology. When will the sizable federal investment in nanotechnology begin to deliver tangible returns? A big part of the answer lies within the domain of instrumentation and metrology, NIST Director Arden L. Bement Jr. told workshop attendees.

“To be sure, new and better measurement tools are needed to sustain advances and discoveries in the laboratory—to distinguish artifact from novel phenomenon, for example, and to enable replication and verification of research results across laboratories,” he said. “Without such tools, science will not acquire the detailed knowledge it needs of the exotic properties and the odd behavior of matter at the nanoscale.” For the full text of Bement’s remarks, go to

blue divider

Back to Top of Page

(Return to NIST News Page)

Editor: Gail Porter

Date created: 1/30/2004