The quantum world gets a bit more interesting today. Scientists at Northwestern University have figured out a simple way to stop a molecular tumbling motion. Shine a laser on it.
The single laser cools the molecule from room temperature to minus 452 degrees in a fraction of a second, halting the molecule’s motion.
“It’s counterintuitive that the molecule gets colder, not hotter when we shine intense laser light on it,” said Brian Odom, lead on the research team. “We modify the spectrum of a broadband laser, such that nearly all the rotational energy is removed from the illuminated molecules. We are the first to stop a molecular tumbling in such a powerful yet simple way.”
Stopping molecules has never been the problem. Stopping the rotation of a tumbling one has. Now that scientists can stop the tumbling, now what? The press release from Northwestern University describes how the precise control of molecules is “essential to using molecules in the construction of super fast quantum computers — machines whose processing power would be exponentially faster than today’s computers.”
Odom and his team used aluminum monohydride molecules for the test. They are inexpensive, plus they don’t vibrate when a laser hits it. It’ll be interesting to see how the technique works for molecules that do vibrate when interacting with a laser.
“By choosing the right molecule we were able to stop the molecules from rotating without worrying about the vibrations,” said Odom.
Quantum computers gets the most attention for possible uses of precise control of molecules. But, other fields including chemistry can also see the benefits.
The team published their findings in the journal Nature Communications.
Image credit: Erik Lucero