Inverse opal optical Tamm state for sensing applications

We report the excitation of optical Tamm states (OTS) in inverse opal (IO) - based three-dimensional photonic crystal on a flat metal substrate, validated through both numerical simulations and experimental observations. Large area, uniform Tamm inverse opal (Tamm-IO) structures were fabricated without the use of any corrosive chemicals. Upon infiltration of non-reactive solvents such as methanol and ethanol into the IO, a noticeable shift of the OTS, consistent with our simulations is observed, and the temporal dynamics of the same have been investigated. The experimentally obtained sensitivity is ~ 110 nm/RIU which is of the same order as the computed value, making the IO OTS to be an attractive sensing tool.