Using Surface Plasmon Band Gap for robust, on-field, biological and chemical detection
Surface Plasmons (SP) are electromagnetic waves that propagate on the interface between a metal, such as gold, and a dielectric. Because they are waves concentrated around the interface, they are very sensitive to minute changes of dielectric constant on the interface. Monitoring surface plasmon propagation can therefore be used to measure the binding of molecules on top of a metallic surface, a technique called Surface Plasmon Resonance (SPR) detection. This technique is however too fragile and bulky to be incorporated in a network of embedded sensors. By using the properties of the propagation of SP in periodic media, we are exploring a new paradigm for surface plasmon sensing that will enable sensors that are much more robust and reliable. Because these sensors can be adapted to the specific detection of most molecules, we believe that they will become ultimately a powerful solution for embedded biological sensing.