Cholesteric liquid crystals,consisting of chiral molecules,form self-assembled periodic structures exhibiting a photonic bandgap.Their selective reflectivity makes them well suited for a variety of applications;their ...Cholesteric liquid crystals,consisting of chiral molecules,form self-assembled periodic structures exhibiting a photonic bandgap.Their selective reflectivity makes them well suited for a variety of applications;their optical response is therefore of considerable interest.The reflectance and transmittance of finite cholesteric cells is usually calculated numerically.Evanescent modes in the bandgap make the calculations challenging;existing matrix propagation methods cannot describe the reflection and transmission coefficients of thick cholesteric cells accurately.Here we present analytic solutions for the electromagnetic fields in cholesteric cells of finite thickness,and use them to calculate the transmission and reflection spectra.The use of analytic solutions allows for the accurate description of arbitrarily thick cholesteric cells,which would not be possible with only direct numerical methods.展开更多
基金We acknowledge support from the NSF under grant IIP 1114332.
文摘Cholesteric liquid crystals,consisting of chiral molecules,form self-assembled periodic structures exhibiting a photonic bandgap.Their selective reflectivity makes them well suited for a variety of applications;their optical response is therefore of considerable interest.The reflectance and transmittance of finite cholesteric cells is usually calculated numerically.Evanescent modes in the bandgap make the calculations challenging;existing matrix propagation methods cannot describe the reflection and transmission coefficients of thick cholesteric cells accurately.Here we present analytic solutions for the electromagnetic fields in cholesteric cells of finite thickness,and use them to calculate the transmission and reflection spectra.The use of analytic solutions allows for the accurate description of arbitrarily thick cholesteric cells,which would not be possible with only direct numerical methods.