Features of magnetically induced exceptional points in cholesteric liquid crystals

Abstract In this work, the photonic properties of cholesteric liquid crystals (CLCs) in an external magnetic field parallel to the helix axis are investigated for the first time in the short-wavelength band of the spectrum, where exceptional points (EPs) are found. It was shown that at EP the real parts of two of four wave numbers touch each over, and their imaginary parts intersect. Here the reflection, transmission and absorption show the same values for two eigenmodes of CLC layer. At anisotropic absorption near the EP there appear points where the magnetically induced transmittance and absorption are observed. The light localization peculiarities as well as photonic density of states (PDOS) peculiarities near these points were also investigated. Near EPs, PDOS for two eigenmodes shows significant changes, especially with different magneto-optical activity parameters.