title: Tunable cavity optomechanics with ultracold atoms.
abstract: We present an atom-chip-based realization of quantum cavity optomechanics with cold atoms localized within a Fabry-Perot cavity. Effective subwavelength positioning of the atomic ensemble allows for tuning the linear and quadratic optomechanical coupling parameters, varying the sensitivity to the displacement and strain of a compressible gaseous medium. We observe effects of such tuning on cavity optical nonlinearity and optomechanical frequency shifts, providing their first characterization in the quadratic-coupling regime.
authors.affiliation: Department of Physics, University of California, Berkeley California 94720, USA.
authors.forename: T P
authors.initials: TP
authors.lastname: Purdy
authors.forename: D W C
authors.initials: DW
authors.lastname: Brooks
authors.forename: T
authors.initials: T
authors.lastname: Botter
authors.forename: N
authors.initials: N
authors.lastname: Brahms
authors.forename: Z-Y
authors.initials: ZY
authors.lastname: Ma
authors.forename: D M
authors.initials: DM
authors.lastname: Stamper-Kurn