Novel Integrated Optical Sensor Based on a Grating Coupler Triplet

A novel approach for accomplishing robust integrated optical biosensors is presented. The principle is based on a symmetric grating coupler structure with the inherent feature of compensating disturbances originating from different kinds of mechanical instabilities. The complete sensor system has no moving parts and provides the high sensitivities typical for integrated optical sensors based on grating couplers. The feasibility of this approach is demonstrated by determining the refractive index of liquids as well as by measuring the specific binding of biomolecules (anti-chicken IgG) to immobilized chicken IgG on the sensor chip surface.