While most people may think of a laser as something that will heat other substances, for the very first time ever one has been used to refrigerate water. Scientists at the University of Washington were able to cool liquid water by roughly 36 degrees Fahrenheit (20 degrees Celsius) using an infrared laser. The group has published a study saying that it’s the “first example of a laser beam that will refrigerate liquids like water under everyday conditions.”
One of the researchers says that they weren’t really sure if it was possible to cool water with a laser, simply because water typically warms when illuminated. This led to the use of an infrared laser, which can be used in biological applications, as opposed to visible light, which has an effect similar to a sunburn.
The infrared laser was pointed at a nanocrystal in a drop of water. 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, in turn, carries more heat away, both from the water and the crystal.
The scientists note that this research could play a part in better studying how cells divide and how molecules and enzymes function, but until now it’s not been possible to slow the process, or refrigerate them in order to study their properties. “Using laser cooling, it may be possible to prepare slow-motion movies of life in action. And the advantage is that you don’t have to cool the entire cell, which could kill it or change its behavior.”
The basic ability to cool a tiny area with accuracy could also be used to prevent microprocessors from overheating, or to create more powerful manufacturing lasers than is currently possible, due to the limit at which they would overheat and melt.
SOURCE University of Washington