title: Spectroscopy using quantum logic.
abstract: We present a general technique for precision spectroscopy of atoms that lack suitable transitions for efficient laser cooling, internal state preparation, and detection. In our implementation with trapped atomic ions, an auxiliary "logic" ion provides sympathetic laser cooling, state initialization, and detection for a simultaneously trapped "spectroscopy" ion. Detection is achieved by applying a mapping operation to each ion, which results in a coherent transfer of the spectroscopy ion's internal state onto the logic ion, where it is then measured with high efficiency. Experimental realization, by using 9Be+ as the logic ion and 27Al+ as the spectroscopy ion, indicates the feasibility of applying this technique to make accurate optical clocks based on single ions.
authors.affiliation: Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305, USA. piet.schmidt@uibk.ac.at
authors.forename: P O
authors.initials: PO
authors.lastname: Schmidt
authors.forename: T
authors.initials: T
authors.lastname: Rosenband
authors.forename: C
authors.initials: C
authors.lastname: Langer
authors.forename: W M
authors.initials: WM
authors.lastname: Itano
authors.forename: J C
authors.initials: JC
authors.lastname: Bergquist
authors.forename: D J
authors.initials: DJ
authors.lastname: Wineland