title: Shear ordering in polymer photonic crystals.
abstract: Optical scattering spectra are recorded in situ on flowing colloidal polymeric nanocomposites which are sheared into photonic crystals at 150 degrees C using a high-pressure quartz-cell multipass rheometer. Broadband spectroscopy of the resonant Bragg scattering peak allows the direct observation of crystal formation and melting of monodisperse core-shell particles. A range of flow conditions of this solventless, highly viscous melt reveals four distinct regimes of crystal growth and decay which match a simple rheological model. Extraction of crystal thickness, order and lattice spacing are validated by one-dimensional electromagnetic simulations.
authors.affiliation: Cavendish Laboratory, University of Cambridge, CB3 0HE Cambridge, United Kingdom.
authors.forename: D R E
authors.initials: DR
authors.lastname: Snoswell
authors.forename: A
authors.initials: A
authors.lastname: Kontogeorgos
authors.forename: J J
authors.initials: JJ
authors.lastname: Baumberg
authors.forename: T D
authors.initials: TD
authors.lastname: Lord
authors.forename: M R
authors.initials: MR
authors.lastname: Mackley
authors.forename: P
authors.initials: P
authors.lastname: Spahn
authors.forename: G P
authors.initials: GP
authors.lastname: Hellmann
mesh_terms: D055595:Mechanical Phenomena; D053761:Nanocomposites / Q000737:chemistry; D055620:Optical Phenomena; D017785:Photons; D011108:Polymers / Q000737:chemistry*; D013696:Temperature; D014783:Viscosity
chemical_list: D011108:Polymers