Atom interferometry is the most sensitive known technique for measuring gravitational forces and inertial forces such as acceleration and rotation. It’s a mainstay of scientific research and is being commercialized as a means of location-tracking in environments where GPS is unavailable. It’s also extremely sensitive to electric fields and has been used to make minute measurements of elements’ fundamental electrical properties.
The most sensitive atom interferometers use exotic states of matter called Bose-Einstein condensates. In the latest issue of Physical Review Letters, MIT researchers present a way to make atom interferometry with Bose-Einstein condensates even more precise, by eliminating a source of error endemic to earlier designs.
Interferometers using the new design could help resolve some fundamental questions in physics, such as the nature of the intermediate states between the quantum description of matter, which prevails at very small scales, and the Newtonian description that everyday engineering depends on.
“The idea here is that Bose-Einstein condensates are actually pretty big,” says William Burton, an MIT graduate student in physics and first author on the paper. “We know that very small things act quantum, but then big things like you and me don’t act very quantum. So we can see how far apart we can stretch a quantum system and still have it act coherently when we bring it back together. It’s an interesting question.”
Joining Burton on the paper are his advisor, professor of physics Wolfgang Ketterle, who won the 2001 Nobel Prize in physics for his pioneering work on Bose-Einstein condensates; Colin Kennedy and Woo Chang Chung, both graduate students in physics; Wenlan Chen, a postdoc at MIT’s Research Laboratory of Electronics; and Samarth Vadia, an undergraduate physics major. All co-authors are members of the MIT-Harvard Center for Ultracold Atoms, which Ketterle directs.