Quantum degenerate Fermi and Bose gases in microscopic traps

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The implications of quantum mechanics continue to challenge our understanding of the world. In 2001, the Nobel Prize in Physics was awarded in recognition of the first observation of a Bose-Einstein condensate (BEC) in a dilute gas. A BEC experiment uses laser light to cool and trap gases of neutral atoms. Laser-cooled atoms are then loaded into a magnetic trap, where they are compressed and further cooled. Finally, at some of the lowest temperatures achievable in a laboratory, the gas becomes quantum degenerate. Ultracold atom experiments capture the imagination of scientists and non-scientists alike, because we can see the quantum world with an ordinary camera. Degenerate gases can act as simulators of technologically relevant materials such as high-temperature superconductors. Eventually the many-body physics we learn with cold atoms may address open questions about these quantum materials. In our lab, we  trap two species (Rubidium 87, a boson, and Potassium 40, a fermion) with a microscopic "chip" trap. We use the Bose gas as a quantum "ice cube" to cool the Fermi gas. The strong confinement created in the chip trap leads to sympathetic cooling rates approximately ten times faster than typical experiments with Fermi gases. We have also shown that the same strong confinement leads to one of the highest efficiency evaporative cooling paths to Bose-Einstein condensation. Over the next five years, we plan to study the many-body physics of these quantum gases, including light scattering properties of cold fermions, non-harmonic traps, and the physics of Bose-Fermi mixtures.