title: Coherent manipulation of electronic States in a double quantum dot.
abstract: We investigate coherent time evolution of charge states (pseudospin qubit) in a semiconductor double quantum dot. This fully tunable qubit is manipulated with a high-speed voltage pulse that controls the energy and decoherence of the system. Coherent oscillations of the qubit are observed for several combinations of many-body ground and excited states of the quantum dots. Possible decoherence mechanisms in the present device are also discussed.
authors.affiliation: NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi 243-0198, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hayashi
authors.forename: T
authors.initials: T
authors.lastname: Fujisawa
authors.forename: H D
authors.initials: HD
authors.lastname: Cheong
authors.forename: Y H
authors.initials: YH
authors.lastname: Jeong
authors.forename: Y
authors.initials: Y
authors.lastname: Hirayama