Quantum Degenerate Gases of Atomic Strontium

This talk will describe the production and properties of a Bose-Einstein condensate of $^{84}$Sr and a quantum degenerate mixture of $^{87}$Sr (fermion) and $^{88}$Sr (boson). $^{88}$Sr has a small negative scattering length leading to a maximum condensate size for our trapping conditions of about 10$^{4}$ atoms. $^{87}$Sr is used to sympathetically cool $^{88}$Sr, but it is also of interest for study of quantum degenerate Fermi gases because it has a large nuclear spin (I=9/2). Alkaline-earth metal atoms and atoms with similar electronic structure are of interest for quantum computing proposals, cold collision studies, and investigation of quantum fluids. There are a wealth of isotopes that allow mass-tuning of interactions and creation of various quantum mixtures. The two-valence electrons lead to a singlet ground state and narrow intercombination transitions to metastable triplet states, offering the promise of low-loss optical Feshbach resonances for manipulating scattering lengths. Fermions often have large nuclear spin, which is decoupled from electronic degrees of freedom and leads to a large degree of symmetry and degeneracy in the interaction Hamiltonian. Work done in collaboration with Y.N. Martinez de Escobar, P.G. Mickelson, M. Yan, B.J. DeSalvo, and S.B. Nagel, Rice University.