Photonic crystal sensors: An overview

Photonic crystals have achieved a lot of research significance due to their projected applications. Their use as sensors is enabled due to their well-defined physical properties such as reflectance/transmittance, superior levels of sensitivity resulting in precise detection limits as well as due to the sparkling visual quality they display in the visible range of wavelengths. The sensor itself is very small when the photonic crystal technology is employed and measurements are possible through coupling the incident and reflected/transmitted light to optical fibers and analyzing them in remote locations. For any sensing technology to be viable in the long-term, it is important to consider the cost-effectiveness of the product and the reliability of measurements over other existing techniques. In this review, a variety of sensing devices based on photonic crystals have been discussed along with the physical parameters of the photonic crystals that enable them.