LOS ANGELES, June 22 (Xinhuanet)-- A group of US physicists announced on Wednesday to have created a new type of matter, a gas of atoms that shows high-temperature superfluidity.

    With this achievement, the researchers at Massachusetts Institute of Technology (MIT) have claimed a champion in the race among world physicists, said Wolfgang Ketterle, a Nobel laureate professor at MIT who led the group.

    Their work, to be reported in the June 23 issue of Nature, is closely related to the superconductivity of electrons in metals. Observations of superfluids may help solve lingering questions about high-temperature superconductivity, which has widespread applications for magnets, sensors and energy-efficient transport of electricity.

    For several years, research groups around the world have been studying cold gases of so-called fermionic atoms with the ultimategoal of finding new forms of superfluidity.

    A superfluid gas can flow without resistance. It can be clearly distinguished from a normal gas when it is rotated. A normal gas rotates like an ordinary object, but a superfluid can only rotate when it forms vortices similar to mini-tornadoes.

    This gives a rotating superfluid the appearance of Swiss cheese,where the holes are the cores of the mini-tornadoes, the researchers said.

    For almost a year, the team had been working on making magneticfields and laser beams very round so the gas could be set in rotation. And in the evening of April 13, they team first saw the superfluid gas.

    "In superfluids, as well as in superconductors, particles movein lockstep. They form one big quantum-mechanical wave," explainedKetterle. Such a movement allows superconductors to carry electrical currents without resistance.

    The MIT team was able to view these superfluid vortices at extremely cold temperatures, when the fermionic gas was cooled to about 50 billionths of a degree Kelvin, very close to absolute zero (-273 degrees C).

    "We have now achieved by far the highest temperature ever," Ketterle said in a statement. Scaled up to the density of electrons in a metal, the superfluid transition temperature in atomic gases would be higher than room temperature.

    The team observed fermionic superfluidity in the lithium-6 isotope comprising three protons, three neutrons and three electrons. Since the total number of constituents is odd, lithium-6 is a fermion.

    Using laser and evaporative cooling techniques, they cooled the gas close to absolute zero. They then trapped the gas in the focus of an infrared laser beam; the electric and magnetic fields of the infrared light held the atoms in place. The last step was to spin a green laser beam around the gas to set it into rotation.A shadow picture of the cloud showed its superfluid behavior: The cloud was pierced by a regular array of vortices, each about the same size.

    The work is based on the group's earlier creation of Bose-Einstein condensates, a form of matter in which particles condenseand act as one big wave. Albert Einstein predicted this phenomenon in 1925. Scientists later realized that Bose-Einstein condensationand superfluidity are intimately related.

    The superfluid Fermi gas created at MIT can also serve as an easily controllable model system to study properties of much denser forms of fermionic matter such as solid superconductors, neutron stars or the quark-gluon plasma that existed in the early universe, the researchers said. Enditem