Tiny compasses could improve brain imaging, navigation, more

A team of engineers and physicists at CU Boulder discovered a way to transform atoms into tiny compasses by using their natural behavior to measure the orientation of surrounding magnetic fields.

The new study hinged on a small chamber containing about one hundred billion rubidium atoms. The researchers discovered that if they tweaked those atoms in just the right way, they could make their internal structures wiggle—an atomic dance that also reveals information about magnetic fields in the environment.

The findings could lead to new kinds of quantum sensors, like devices for mapping the activity of the human brain or navigational tools that help airplanes circle the globe.

“It’s now a question of: ‘How far can we push these atomic systems?’” said Svenja Knappe, research professor in the Paul M. Rady Department of Mechanical Engineering.