Photonics for nano-applications
With the increasing demand for highly integrated sensitive detectors for biomedical and environmental applications, the many promising optical properties of nanostructured photonic materials were explored within the NANOPHOS project. Aiming beyond the established gas sensor concepts, both their linear and non-linear optical responses when introduced into chemical environments were investigated. The project partner efforts have been directed towards the development of sensor devices which register changes in the optical properties of gas sensing materials such as metal oxides and polymers. Based on the testing results, a non-contact remote sensor was designed and developed that enables the realisation of point sensing at room temperature. The sensor's head comprised a thin film of the active sensing medium with a suitable diffractive interface and a retro-reflective element. The interrogation system developed at the laboratories of the National Hellenic Research Foundation included an optical transmitter with a laser source of tuneable wavelength and adjustable power. Laser beam expanders and collimators enhanced the quality of the final focused spot. Furthermore, a reference arm was incorporated to prevent potential laser instabilities and provide the control required for the efficient target detection. Currently available gas sensor technologies have resulted in a multitude of operational standards that fail to consistently cover actual industrial and environmental needs. New photonic sensor device introduced within the NANOPHOS project will enable highly selective detection of a wide range of gaseous chemical agents, such as Ox, NOx, CO, SOx and other pollutants.