Washington, March 8 : A pair of techniques developed by physicist Mark Raizen at The University of Texas at Austin has made it possible to stop and cool most of the atoms of the periodic table.
Raizen stopped atoms by passing a supersonic beam through an "atomic coilgun" and cooled them using "single-photon cooling."
The techniques are a major step forward in atomic physics and have a variety of scientific and technological applications. They could be used to determine the mass of the neutrino, which is the primary candidate for dark matter.
The results are the culmination of years of work trapping and cooling atoms by Raizen and his research group.
To date, cooling atoms near the Absolute Zero (-459 degrees Fahrenheit) has been accomplished using laser cooling, a method that was recognized by the Nobel Prize in Physics in 1997. Despite its enormous success, laser cooling has been limited to a small set of atoms in the periodic table.
But, according to Raizen, his two methods can be used in tandem to trap and cool near Absolute Zero any of the paramagnetic atoms, which make up over 85 percent of the periodic table.
In one set of experiments, a supersonic beam of neon atoms was completely stopped using a 64-stage coilgun.
The coilgun works by shooting a supersonic beam of atoms through a 3-millimeter diameter bore wrapped by 64 magnetic coils made of copper wire. The coils slow the atoms by making them climb a "magnetic hill." The hill is removed before the atoms have time to roll off and regain speed, and the atoms become magnetically trapped.
"The wonderful thing about the coilgun technology is its simplicity," said Raizen. "We use ordinary copper wire for the coils. The hope is that this will allow others to use the technique to trap and cool the other elements," he added.
"Our methods open up whole new avenues of research," said Raizen. "We can control almost any atom and many molecules," he added.