New supergas debuts.When particles of matter cooperate with each other, the result tan be something super. For instance, there's superconductivity, in which coordinated pairs of electrons flow resistance free through a solid, and there's superfluidity superfluidity, tendency of liquid helium below a temperature of 2.19°K; to flow freely, even upward, with little apparent friction. Helium becomes a liquid when it is cooled to 4.2°K;. , in which atoms or molecules flow without friction. Now, Deborah S. Jin Deborah S. Jin (born 1968) is a physicist with the National Institute of Standards and Technology (NIST); Assistant Professor Adjoint, Department of Physics at the University of Colorado; a fellow of the JILA, a NIST joint laboratory with the University of Colorado. In 2003, Dr. and her colleagues at JILA JILA Joint Institute for Laboratory Astrophysics (Space) , a Boulder, Colo.-based joint research operation of the National Institute of Standards and Technology National Institute of Standards and Technology, governmental agency within the U.S. Dept. of Commerce with the mission of "working with industry to develop and apply technology, measurements, and standards" in the national interest. and the University of Colorado University of Colorado may refer to:
This first example of the new super stuff is a gas of some half-million potassium atoms chilled below 50 nanokelvins and influenced by a magnetic field. Jin, Cindy A. Regal, and Markus Greiner describe the novel substance, dubbed a fermionic condensate, in the Jan. 30 Physical Review Letters Physical Review Letters is one of the most prestigious journals in physics.[1] Since 1958, it has been published by the American Physical Society as an outgrowth of The Physical Review. . The new state of matter is reminiscent of a Bose-Einstein condensate (BEC), a type of superfluid su·per·flu·id n. A fluid, such as a liquid form of helium, exhibiting a frictionless flow at temperatures close to absolute zero. su in which an ultracold cloud of atoms or molecules coalesces into a single quantum state (SN: 11/22/03, p.324). Yet the new material isn't a BEC, notes Eric A. Cornell, a BEC pioneer also of JILA. That's because the potassium atoms in the new material coordinate with each other in pair-wise fashion not found in BECs but similar to what takes place between the electrons of a superconductor. On the other hand, Cornell notes, the pairing in the potassium gas is far stronger than that in any superconductor ever observed. The new substance is "neither fish nor fowl," he says. The extraordinary strength of pairing makes this first-ever fermionic condensate of special interest to scientists and engineers because it's a property that scientists expect to find in future superconductors that might operate at room temperature. This new work may provide clues for how to attain that long-sought goal, Jin says. ALL ABOARD! Rising peak (back to front) shows an increasing fraction of potassium atoms piling into a new state of matter as a magnetic field reaches a specific strength. [ILLUSTRATION OMITTED] |
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