Concept of the experiment, A: an ensemble of 1D Bose gases in tubes formed by two pairs of counterpropagating and interfering laser beams. In each tube, a single strongly interacting impurity (green sphere) is immersed in the correlated host gas (black spheres) and is accelerated by gravity (green arrow). Inset: Scattering length as for collisions between the atoms in the host gas (dashed line) and between the impurity and the host atoms (solid line) as a function of the magnetic field B.* [Reprinted by permission from AAAS ©2017.]
Physics Concentrators: Michael Albergo, Eric Anschuetz, Stephanie Carr, Daniel Chen, Francesca Childs, Andrew Cho, Jeremy Dietrich, Deanna Emery, Shadi Fadaee, Benjamin Garber, Juliana Garcia-Mejia, Julia Grotto, Christian Hallas, Constantin Knoll, Richard Koh, Elgin Korkmazhan, Charles Law, Max L'Etoile, Jiang Li, Henry Lin, Eric Lu, Andrew Mayo, Saahil Mehta, Alexander Nie, Jenny Nitishinskaya, Maxwell Nye, Eugene O'Friel, Makinde Ogunnaike, Meg Panetta, Gregory Parker, Thomas Peeples, Gray Putnam, Jason Qu, Steven Rachesky, Daniel Rothchild, George Torres, Shreya Vardhan, Jennifer Walsh, Jonathan Ward, Noah Wuerfel, and Wayne Zhao.
At very low temperatures, quantum matter can show radically different, and often counterintuitive, behavior compared to traditional liquids, solids, and gases. Such quantum phases of matter (e.g., superfluids and superconductors) are used in practical applications such as levitating trains and medical imaging. In the field of quantum simulation, researchers are attempting to engineer phases of matter that are even more exotic. One appealing approach is to start with a standard quantum fluid and "drive it" by shaking it, rotating it, or subjecting it to an external field. However, this method faces a serious difficulty: the phase is unstable.
Physicists considering a foray into the study of molecules are often warned that “a diatomic molecule is one atom too many!”. Now John Doyle and colleagues at Harvard University have thrown this caution to the wind and tackled laser cooling of a triatomic molecule with success, opening the door to the study of ultracold polyatomic molecules.