TY - JOUR
T1 - Interplay of index contrast with periodicity in polymer photonic crystals
AU - Finlayson, Christopher Edward
AU - Haines, Andrew I.
AU - Snoswell, David R. E.
AU - Kontogeorgos, Andreas
AU - Vignolini, Silvia
AU - Baumberg, Jeremy J.
AU - Spahn, Peter
AU - Hellmann, G. Peter
PY - 2011
Y1 - 2011
N2 - We report how the strength of resonant Bragg reflection from polymeric photonic crystals (polymer opals) varies linearly with the refractive-index contrast, Δn, in contrast to the quadratic buildup of Fresnel reflections scaling as (Δn)2. This occurs due to the interplay of disorder and periodicity, in agreement with a simple 1-dimensional periodic model. Goniometry experiments show that opal films exhibit “cones” of resonantly scattered light, which extend to ±20° angular deviation from the specular direction. The intensity of the scattering cones varies super-linearly with Δn. Such medium contrast photonic crystals are of significant interest for understanding structural colors exhibited in nature, by structures with inherent disorder.
AB - We report how the strength of resonant Bragg reflection from polymeric photonic crystals (polymer opals) varies linearly with the refractive-index contrast, Δn, in contrast to the quadratic buildup of Fresnel reflections scaling as (Δn)2. This occurs due to the interplay of disorder and periodicity, in agreement with a simple 1-dimensional periodic model. Goniometry experiments show that opal films exhibit “cones” of resonantly scattered light, which extend to ±20° angular deviation from the specular direction. The intensity of the scattering cones varies super-linearly with Δn. Such medium contrast photonic crystals are of significant interest for understanding structural colors exhibited in nature, by structures with inherent disorder.
UR - http://hdl.handle.net/2160/11204
U2 - 10.1063/1.3672215
DO - 10.1063/1.3672215
M3 - Letter
SN - 0003-6951
VL - 99
JO - Applied Physics Letters
JF - Applied Physics Letters
M1 - 261913
ER -