Working at temperatures approaching absolute zero, a team led by MIT Physics professor and Nobel laureate Wolfgang Ketterle has acheived the first magnetic trapping of an elusive “superfluid” phase of matter. MIT News reports:
MIT physicists have created a superfluid gas, the so-called Bose-Einstein condensate, for the first time in an extremely high magnetic field. The magnetic field is a synthetic magnetic field, generated using laser beams, and is 100 times stronger than that of the world’s strongest magnets. Within this magnetic field, the researchers could keep a gas superfluid for a tenth of a second — just long enough for the team to observe it. The researchers report their results this week in the journal Nature Physics.
A superfluid is a phase of matter that only certain liquids or gases can assume, if they are cooled to extremely low temperatures. At temperatures approaching absolute zero, atoms cease their individual, energetic trajectories, and start to move collectively as one wave.
Superfluids are thought to flow endlessly, without losing energy, similar to electrons in a superconductor. Observing the behavior of superfluids therefore may help scientists improve the quality of superconducting magnets and sensors, and develop energy-efficient methods for transporting electricity.
But superfluids are temperamental, and can disappear in a flash if atoms cannot be kept cold or confined. The MIT team combined several techniques in generating ultracold temperatures, to create and maintain a superfluid gas long enough to observe it at ultrahigh synthetic magnetic fields.
“Going to extremes is the way to make discoveries,” says team leader Wolfgang Ketterle, the John D. MacArthur Professor of Physics at MIT. “We use ultracold atoms to map out and understand the behavior of materials which have not yet been created. In this sense, we are ahead of nature.”
OCW is honored to have a two-course sequence by Prof. Ketterle, 8.421 Atomic and Optical Physics I and 8.422 Atomic and Optical Physics II. Both courses include complete video lectures, and 8.422 also includes his teaching insights on a This Course at MIT page.
If you’d like to dive straight into Bose-Einstein condensates, start with 8.422’s Lecture 19: