Modelling andMeasurement ofElectronically Tunable Photonic Crystals

Thispaperpresents details ofthemodelling that hasbeenusedtoextract particle spacing frommeasured diffraction patterns intunable photonic crystal structures. Thephotonic crystals areformed fromcolloidal suspensions oflatex spheres withtheapplication ofrotating Alternating Current (AC)electric fields. Theparticle spacing canberapidly changed byaltering theamplitude oftheAC field. Initially simple IDdiffraction grating theory isusedtoextract theparticle spacing. Thisisfollowed byFinite Element (FE)modelling whichshows goodagreement withthesimple theory. Full 3Dmodelling wasinvestigated butonlysmall number ofspheres could bemodelled.