Lasers used to refrigerate water for first time ever

The findings have implications for many other areas, such as in microprocessors where laser beam could be used to cool specific components in computer chips to prevent overheating and to make them more efficient in processing.

Laser has been invented nearly five decades ago and has been successfully used to heat up materials. Researchers ended up cooling that small amount of water by about 36 degrees. “It was really an open question as to whether this could be done because normally water warms when illuminated”.

A team of scientists keen to change the way lasers have always worked has developed a laser that actually cools down the area it is being fired at, leaving hope for science fiction fans of an actual freeze ray.

Scientists inch closer to laser freeze ray with cool laser in a breakthrough experiment at the University of Washington.

Peter Pauzauskie, senior researcher involved in the study and materials science and engineering expert at University of Washington, said that his team was able to refrigerate liquids with laser under normal conditions for the first time ever. In its current form, it uses a lot of energy.

Pauzauskie says, “There’s a lot of interest in how cells divide and how molecules and enzymes function, and it’s never been possible before to refrigerate them to study their properties”.

Whether they’re mounted on sharks or emanating from the Death Star, lasers can deliver destructive levels of heat.

This research and the ability to accurately cool a tiny area have several potential applications. In fact, one day the technology could be used to enable high-power lasers for manufacturing, telecommunications or defense applications. Thanks to the breakthrough experiment, scientists could cool one fragment of a cell during cell division or while the cell undergoes natural repairing processes. The infrared light emitted by the cooling laser is set at a frequency such that atoms that happen to be moving toward the light source will emit a photon, producing a distinctive glow and decreasing the speed (and temperature) of the atom.

“Using laser cooling, it may be possible to prepare slow-motion movies of life in action”, Pauzauskie added.

Researchers chose to use infrared light because visible light could give cells a damaging ‘sunburn’.

They demonstrated that the laser could refrigerate saline solution and cell culture media that are commonly used in genetic and molecular research. The atoms in the crystal absorbed the light’s photons, but when they are then released, it’s with more energy than when the photons first entered.

This higher-energy glow carries heat away from both the crystal and the water surrounding it. The laser refrigeration process was first demonstrated in vacuum conditions at Los Alamos National Laboratory in 1995, but it has taken almost 20 years to demonstrate this process in liquids.