title: Direct evidence of interlevel exciton transitions mediated by single phonons in a semiconductor quantum dot using resonance fluorescence spectroscopy.
abstract: Using resonance fluorescence, we investigate how acoustic phonons mediate couplings between multiple electronic levels in a semiconductor quantum dot. We show the first direct evidence of population up-conversion in a single quantum dot, which we attribute to absorption of single acoustic phonons. Moreover, through a rate equation analysis, we find that below 20 K such single-phonon mediated couplings between the exciton ground state and the first excited state are primarily responsible for decoherence of the exciton quantum state.
authors.affiliation: Physics Department, University of Texas at Austin, 1 University Station C1600, Austin, Texas 78712, USA. edward.flagg@nist.gov
authors.forename: Edward B
authors.initials: EB
authors.lastname: Flagg
authors.forename: John W
authors.initials: JW
authors.lastname: Robertson
authors.forename: Sébastien
authors.initials: S
authors.lastname: Founta
authors.forename: Wenquan
authors.initials: W
authors.lastname: Ma
authors.forename: Min
authors.initials: M
authors.lastname: Xiao
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Salamo
authors.forename: Chih-Kang
authors.initials: CK
authors.lastname: Shih