Eur. Phys. J. E 12, 553 (2003)
We discuss the properties of photonic defect modes in cholesteric liquid crystals. Twist defects, isotropic defect layers, and combinations of both are considered. After deriving the reflection and transmission properties of the defects, we study the effect of finite sample thickness on the defect mode's amplitude and on the required polarization of incident light to excite the defect mode.