Unidirectional Narrowband Perfect Absorption in Quasi-random Structures - Interplay of Gap States and Tamm Plasmon Modes

Quasi-random non-conservative planar photonic structures have been investigated for ultra-narrowband perfect absorption in the technologically important infrared domains. Obtained gap state induced resonances exhibit novel features such as unidirectional absorption, an asymmetric Fano lineshape and an anti-crossing behavior with the coexistent Tamm plasmon mode.