title: Resonant excitation and imaging of nonequilibrium exciton spins in single core-shell GaAs-AlGaAs nanowires.
abstract: Nonequilibrium spin distributions in single GaAs/AlGaAs core-shell nanowires are excited using resonant polarized excitation at 10 K. At all excitation energies, we observe strong photoluminescence polarization due to suppressed radiative recombination of excitons with dipoles aligned perpendicular to the nanowire. Excitation resonances are observed at 1- or 2-LO phonon energies above the exciton ground states. Using rate equation modeling, we show that, at the lowest energies, strongly nonequilibrium spin distributions are present and we estimate their spin relaxation rate.
authors.affiliation: Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221-0011, USA.
authors.forename: Thang Ba
authors.initials: TB
authors.lastname: Hoang
authors.forename: Lyubov V
authors.initials: LV
authors.lastname: Titova
authors.forename: Jan M
authors.initials: JM
authors.lastname: Yarrison-Rice
authors.forename: Howard E
authors.initials: HE
authors.lastname: Jackson
authors.forename: Alexander O
authors.initials: AO
authors.lastname: Govorov
authors.forename: Yong
authors.initials: Y
authors.lastname: Kim
authors.forename: Hannah J
authors.initials: HJ
authors.lastname: Joyce
authors.forename: H Hoe
authors.initials: HH
authors.lastname: Tan
authors.forename: Chennupati
authors.initials: C
authors.lastname: Jagadish
authors.forename: Leigh M
authors.initials: LM
authors.lastname: Smith