Molecules wrangled into single quantum state in breakthrough experiment
Quantum technology is bursting with potential, but controlling atoms and molecules keeps proving tricky. In a breakthrough new study, physicists have successfully wrangled thousands of molecules into a single unified quantum state for the first time.
The key to the new development is a strange state of matter known as a Bose-Einstein condensate (BEC). When a low density cloud of atoms is cooled to just a hair above absolute zero, they settle into the same quantum state. In essence, they begin to act like one giant atom, which brings hard-to-measure quantum behavior up to the macro scale where it can be observed more easily.
But to realize the most intriguing applications of quantum technology, scientists will need to master more complex molecules, which themselves are made up of atoms. And now, researchers at the University of Chicago have succeeded in doing just that.
“Atoms are simple spherical objects, whereas molecules can vibrate, rotate, carry small magnets,” says Cheng Chin, senior author of the study. “Because molecules can do so many different things, it makes them more useful, and at the same time much harder to control.”
To wrestle molecules into cooperating, the team added two new steps to the normal recipe for producing Bose-Einstein condensates. First, they chilled the system down even colder than usual – to just 10 nanokelvins, an absolutely tiny fraction above 0 K. That helped more of the atoms pair up into molecules.
Then, they confined these molecules into a flat surface, so they can only move in two dimensions, which helps keep them stable for longer. The end result is a 2D molecular Bose-Einstein condensate, made up of several thousand molecules with exactly the same orientation and vibrational frequency. This, the team says, could then be used for a range of quantum applications.
“It’s the absolute ideal starting point,” says Chin. “For example, if you want to build quantum systems to hold information, you need a clean slate to write on before you can format and store that information.”
The research was published in the journal Nature.
Source: University of Chicago