title: Experimental demonstration of a controlled-NOT wave-packet gate.
abstract: We report the experimental demonstration of a controlled-NOT (CNOT) quantum logic gate between motional and internal-state qubits of a single ion where, as opposed to previously demonstrated gates, the conditional dynamics depends on the extent of the ion's wave packet. Advantages of this CNOT gate over one demonstrated previously are its immunity from Stark shifts due to off-resonant couplings and the fact that an auxiliary internal level is not required. We characterize the gate logic through measurements of the postgate ion state populations for both logic basis and superposition input states, and we demonstrate the gate coherence via an interferometric measurement.
authors.affiliation: NIST, Time and Frequency Division, Ion Storage Group, Boulder, Colorado 80305, USA.
authors.forename: B
authors.initials: B
authors.lastname: DeMarco
authors.forename: A
authors.initials: A
authors.lastname: Ben-Kish
authors.forename: D
authors.initials: D
authors.lastname: Leibfried
authors.forename: V
authors.initials: V
authors.lastname: Meyer
authors.forename: M
authors.initials: M
authors.lastname: Rowe
authors.forename: B M
authors.initials: BM
authors.lastname: Jelenković
authors.forename: W M
authors.initials: WM
authors.lastname: Itano
authors.forename: J
authors.initials: J
authors.lastname: Britton
authors.forename: C
authors.initials: C
authors.lastname: Langer
authors.forename: T
authors.initials: T
authors.lastname: Rosenband
authors.forename: D J
authors.initials: DJ
authors.lastname: Wineland