title: Exploring Crystal Phase Switching in GaP Nanowires.
abstract: The growth of wurtzite/zincblende (WZ and ZB, respectively) superstructures opens new avenues for band structure engineering and holds the promise of digitally controlling the energy spectrum of quantum confined systems. Here, we study growth kinetics of pure and thus defect-free WZ/ZB homostructures in GaP nanowires with the aim to obtain monolayer control of the ZB and WZ segment lengths. We find that the Ga concentration and the supersaturation in the catalyst particle are the key parameters determining growth kinetics. These parameters can be tuned by the gallium partial pressure and the temperature. The formation of WZ and ZB can be understood with a model based on nucleation either at the triple phase line for the WZ phase or in the center of the solid-liquid interface for the ZB phase. Furthermore, the observed delay/offset time needed to induce WZ and ZB growth after growth of the other phase can be explained within this framework.
authors.affiliation: Department of Applied Physics Eindhoven, University of Technology , 5600 MB Eindhoven, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: Assali
authors.affiliation: Department of Applied Physics Eindhoven, University of Technology , 5600 MB Eindhoven, The Netherlands.
authors.forename: L
authors.initials: L
authors.lastname: Gagliano
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas, UNICAMP , 13083-859 Campinas, São Paulo, Brazil.
authors.forename: D S
authors.initials: DS
authors.lastname: Oliveira
authors.affiliation: Department of Applied Physics Eindhoven, University of Technology , 5600 MB Eindhoven, The Netherlands.|Philips Innovation Services Eindhoven , High Tech Campus 11, 5656AE Eindhoven, The Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Verheijen
authors.affiliation: CNRS-Laboratoire d'Analyse et d'Architecture des Systèmes (LAAS), Université de Toulouse , 7 avenue du colonel Roche, F-31400 Toulouse, France.
authors.forename: S R
authors.initials: SR
authors.lastname: Plissard
authors.affiliation: Department of Applied Physics Eindhoven, University of Technology , 5600 MB Eindhoven, The Netherlands.
authors.forename: L F
authors.initials: LF
authors.lastname: Feiner
authors.affiliation: Department of Applied Physics Eindhoven, University of Technology , 5600 MB Eindhoven, The Netherlands.|Kavli Institute of Nanoscience, Delft University of Technology , 2600 GA Delft, The Netherlands.
authors.forename: E P A M
authors.initials: EP
authors.lastname: Bakkers
keywords: gallium phosphide; monolayer growth; semiconductor nanowire; supersaturation; wurtzite; zincblende