The low (temperature) road toward bose-einstein condensation in optically and magnetically trapped cesium atoms
There is considerable reason to pursue the extreme limits of low temperature and high density that can be achieved in an atomic vapor. First there is the intrinsic interest in the trapping and cooling of atoms, and the behavior of atoms in new regimes of temperature. Much of this is discussed extensively elsewhere in this volume. Second, many interesting applications of laser cooled and trapped atoms require very cold high density samples. For example, cooled and trapped atoms are ideal for spectroscopy of weak transitions, such as those involved in measurement of parity nonconservation in atoms. Clearly, colder and denser samples will enhance any such experiment with trapped atoms. Finally, the ultimate limit of high density and low temperature is of great interest in its own right. This is Bose Einstein Condensation (BEC) of a trapped vapor sample of bosonic atoms. The ability, in principle, to cross the phase boundary for BEC at several widely spaced points in the temperature-density plane offers the tantalizing prospect of studying the phase transition while varying the relative significance of interparticle interactions. Although these interactions may well prevent BEC, it will be very interesting to see exactly what will happen when one reaches the necessary condition of the deBroglie wavelength of the atoms exceeding the interparticle spacing.
