title: InP Nanoflag Growth from a Nanowire Template by in Situ Catalyst Manipulation.
abstract: Quasi-two-dimensional semiconductor materials are desirable for electronic, photonic, and energy conversion applications as well as fundamental science. We report on the synthesis of indium phosphide flag-like nanostructures by epitaxial growth on a nanowire template at 95% yield. The technique is based on in situ catalyst unpinning from the top of the nanowire and its induced migration along the nanowire sidewall. Investigation of the mechanism responsible for catalyst movement shows that its final position is determined by the structural defect density along the nanowire. The crystal structure of the "flagpole" nanowire is epitaxially transferred to the nanoflag. Pure wurtzite InP nanomembranes with just a single stacking fault originating from the defect in the flagpole that pinned the catalyst were obtained. Optical characterization shows efficient highly polarized photoluminescence at room temperature from a single nanoflag with up to 90% degree of linear polarization. Electric field intensity enhancement of the incident light was calculated to be 57, concentrated at the nanoflag tip. The presented growth method is general and thus can be employed for achieving similar nanostructures in other III-V semiconductor material systems with potential applications in active nanophotonics.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kelrich
authors.forename: Ofir
authors.initials: O
authors.lastname: Sorias
authors.affiliation: Department of Materials Science and Metallurgy, University of Cambridge , Cambridge CB3 0FS, United Kingdom.
authors.forename: Yonatan
authors.initials: Y
authors.lastname: Calahorra
authors.forename: Yaron
authors.initials: Y
authors.lastname: Kauffmann
authors.forename: Ran
authors.initials: R
authors.lastname: Gladstone
authors.forename: Shimon
authors.initials: S
authors.lastname: Cohen
authors.forename: Meir
authors.initials: M
authors.lastname: Orenstein
authors.forename: Dan
authors.initials: D
authors.lastname: Ritter
keywords: InP; catalyst unpinning; field enhancement; linear polarization; nanoflag; nanomembrane; selective area VLS growth