Integrated Multimode Interference Sensor For Bio/Chemical Applications

A novel fiber based MMI optical sensor for bio/chemical applications is demonstrated. The operating mechanism is based on the self-imaging phenomena that occurs in multimode fibers (MMF). However, the MMI sensor is highly wavelength dependent since there is D2 dependence on the wavelength response of the sensor. Therefore, using a specialty fiber, when the fiber is immersed in liquids with different refractive indexes the effective diameter is increased and the MMI response is modified. We show sensitivities on the order of 10-5, which is ideal for label-free bio/chemical sensing applications. © 2009 CBMS