New Way Found To Cool Atoms And Molecules

TECH SPACE

The technique might lead to advances in atomic clocks, which are used to standardize time. Photo credit: NIST

Austin, Texas (UPI) Aug 15, 2005
Physicists at The University of Texas say they've found a new technique for cooling atoms and molecules, allowing more effective quantum physics studies.

The researchers report finding a way to use lasers to form walls that allow atoms and molecules to pass through in one direction, but do not allow them to return.

The technique might lead to advances in atomic clocks, which are used to standardize time.

Dr. Mark Raizen of the university's Center for Nonlinear Dynamics and his colleagues described the one-way wall technique in Physical Review Letters and Europhysics Letters published earlier this year.

Raizen's one-way wall extends the capabilities of laser and evaporative cooling, which have been limited to cooling a small number of atoms in the periodic table.

"The beauty of the one-way atomic wall," Raizen said, "is that there is almost no increase in kinetic energy."

With no increase in kinetic energy comes no increase in heat. By expanding and contracting the space holding the trapped atoms and molecules, the temperature can be lowered to near absolute zero.

It's at such ultra cold temperatures - minus 459 degrees Fahrenheit - that quantum physicists can manipulate atoms and molecules.

All rights reserved. Copyright 2005 by United Press International. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by United Press International. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of by United Press International.

TIME AND SPACE

Tandem Ions May Lead The Way To Better Atomic Clocks

Boulder CO (SPX) Jul 29, 2005
Physicists at the Commerce Department's National Institute of Standards and Technology (NIST) have used the natural oscillations of two different types of charged atoms, or ions, confined together in a single trap, to produce the "ticks" that may power a future atomic clock.