title: Trapped-ion state detection through coherent motion.
abstract: We demonstrate a general method for state detection of trapped ions that can be applied to a large class of atomic and molecular species. We couple a spectroscopy ion (27Al+) to a control ion (25Mg+) in the same trap and perform state detection through off-resonant laser excitation of the spectroscopy ion that induces coherent motion. The motional amplitude, dependent on the spectroscopy ion state, is measured either by time-resolved photon counting or by resolved sideband excitations on the control ion. The first method provides a simplified way to distinguish clock states in 27Al+, which avoids ground-state cooling and sideband transitions. The second method reduces spontaneous emission and optical pumping on the spectroscopy ion, which we demonstrate by nondestructively distinguishing Zeeman sublevels in the (1)S0 ground state of 27Al+.
authors.affiliation: Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305, USA. dhume@kip.uni-heidelberg.de
authors.forename: D B
authors.initials: DB
authors.lastname: Hume
authors.forename: C W
authors.initials: CW
authors.lastname: Chou
authors.forename: D R
authors.initials: DR
authors.lastname: Leibrandt
authors.forename: M J
authors.initials: MJ
authors.lastname: Thorpe
authors.forename: D J
authors.initials: DJ
authors.lastname: Wineland
authors.forename: T
authors.initials: T
authors.lastname: Rosenband