In a cooled and trapped cloud of ytterbium atoms, the transition from a superfluid to an insulating state has been observed, opening up new possibilities for precision measurements, optical clocks, and quantum computing.
Inelastic light scattering is used to study correlated phases of one-dimensional Bose gases. This spectroscopic technique can distinguish superfluid and insulating phases and allow identification of the transition from one to the other.
Trapped cold atom gases mimic much of the behavior of electrons in a solid, but because the atoms are neutral, it is difficult to imitate the physics of electrons moving in a magnetic field. Now, experiments show that a suitable combination of lasers can create an artificial magnetic field for cold atoms.
Stochastic resonance, in which a periodic signal applied to a nonlinear system can be amplified by adding noise, has been observed in a mechanical system and predicted to occur in a Bose-Einstein condensate.
Trapping atoms inside of a submicron volume for applications such as quantum computing and nanoscale optics poses a host of experimental difficulties. One idea for doing this takes advantage of the strong electric field that can be excited on the surface of metal nanoparticles.
Ultracold atoms in an optical lattice share a lot of physics with electrons in a crystalline solid and it is a system that is often much easier to control. By forcing an optical lattice to vary with time, it is possible to engineer the energy of cold atoms and essentially bring them to a halt.
Disorder in a crystal tends to localize electrons and drive a transition from a metallic to an insulating state. The same localization can occur in cold atom gasses in a periodic optical trap, but since the trap is tunable it may be possible to explore this effect in multiple dimensions.
Spin dependence of atomic and electronic interactions can give rise to propagating regions of aligned spins in solids called spin waves. These have now been observed in a gas of ultracold fermionic atoms.