A group of widegap polar semiconductors, such as GaN, ZnO and CuCl, are known to possess large nonlinear optical constants, very stable excitons and ferromagnetism up to room temperature, but unfortunately there is still very limited work to draw out these higher-order optical properties in the form of device applications. In this work, trials will be made for the enhancement of the interaction between light and matter within these materials by the introduction of the photonic nanostructures, in order to develop the novel optical devices with active functions, such as wavelength conversion devices, polaritonic lasers and optical isolators.