A thorough understanding of nanoscience and the creation of novel nanoscale materials and devices requires a deep understanding of the laws of quantum mechanics that govern ultrasmall systems. Acquiring that understanding is a major challenge. As human beings living in a classical world, we have no deep and natural intuition of the workings of the quantum world. Computers aren't much help either. Even the best of them can't handle the quantum mathematical descriptions of more than four or five atomic or subatomic particles.
Ultracold atoms and molecules are an excellent model system for the study of quantum mechanics, however. They are much larger than the nanoscale systems, which makes them easier to study. In Bose-Einstein condensates, for example, thousands of atoms collapse into a single one millimeter quantum wave, which is big enough for the eye to see. Degenerate Fermi gases, whose behaviors are entirely quantum mechanical, are large enough to see with an optical microscope, as are optical lattices. Optical lattices can contain a single ultracold atom or molecule per lattice site, with spacing between lattice sites on the order of 500–1000 nm. JILA scientists Dana Anderson, Eric Cornell, Deborah Jin, Cindy Regal, Ana Maria Rey, and Jun Ye study these ultracold systems to observe quantum behavior in action. Their growing understanding of quantum behavior is leading to innovative quantum simulations, including atomtronics devices, which are cold-atom analogs of conventional electronics devices, and novel quantum computing schemes. Their insights into these systems promise to shed light on the behavior of electrons passing through the switch region of tiny transistors as well as the dynamics of nanoscale biomolecules, materials, and electronic devices.