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In a famous paper, P. W. Anderson coined the phrase “more is different”, capturing the essence in many research fields in physics: A system of many constituents of the same nature (many electrons, atoms, etc) is not just “more of the same”; it is altogether a different system, with strikingly different physical phenomena. In order to understand the behavior of a complex system (from electrons in metals, to a pile of rice), it is not enough to know the basic laws of physics. It is necessary to  develop new theoretical framework and base it on extensive experimental data.

A very important class of complex systems is that of interacting fermions. Examples include electrons in metals, a liquid of  3He, neutrons in a neutron star, and more. We are studying the many-body physics of strongly interacting Fermions using an ultracold gas of potassium 40. Using lasers and magnetic fields, we trap and cool down the atoms in a vacuum chamber. We can alter their interaction with each other, their geometrical configuration, temperature, and many other parameters. When the atoms reach low enough temperature, they form a fermionic superfluid. We can observe and study this fascinating physics directly with a CCD camera.

Our labs and offices are located in the solid state institution building, which is adjacent to the Lidow physics building in the main campus. Click here for more information on how to get here.

Solid State Institute Building