title: Second-harmonic generation imaging of semiconductor nanowires with focused vector beams.
abstract: We use second-harmonic generation (SHG) with focused vector beams to investigate individual vertically aligned GaAs nanowires. Our results provide direct evidence that SHG from oriented nanowires is mainly driven by the longitudinal field along the nanowire growth axis. Consequently, focused radial polarization provides a superior tool to characterize such nanowires compared to linear polarization, also allowing this possibility in the native growth environment. We model our experiments by describing the SHG process for zinc-blende structure and dipolar bulk nonlinearity.
authors: Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland.
authors: Godofredo
authors: G
authors: Bautista
authors: Jouni
authors: J
authors: Mäkitalo
authors: Ya
authors: Y
authors: Chen
authors: Veer
authors: V
authors: Dhaka
authors: Marco
authors: M
authors: Grasso
authors: Lasse
authors: L
authors: Karvonen
authors: Hua
authors: H
authors: Jiang
authors: Mikko J
authors: MJ
authors: Huttunen
authors: Teppo
authors: T
authors: Huhtio
authors: Harri
authors: H
authors: Lipsanen
authors: Martti
authors: M
authors: Kauranen
keywords: Second-harmonic generation; modeling; nonlinear imaging; radial polarization; semiconductor