Photonic crystal gas sensors

The bandstructure of photonic crystals offers intriguingpossibilities for the manipulation of electromagnetic waves. During the last years, research has mainly focussed on theapplication of these photonic crystal properties in the telecomare a. We suggest utilization of photonic crystals for sensorapplications such as qu alitative and quantitative gas and liquidanalysis. Taking advantage of the low group velocity and certainmode distributions for some k-points in the bandstructure of a photonic crystal should enable the realization of verycompact sensor devices. We show different device configurations of a photonic crystal based on macro porous silicon that fulfill the demands to serve as a compact gas sensor.