Breath figures onto optical fibers for miniaturized sensing probes

The "lab-on-fiber" technology has been recently proposed as a valuable route for the realization of novel and highly functionalized technological platforms completely integrated in a single optical fiber in communication and sensing applications. As a follow-up of the proposed technological approach, here, we present recent results on the fabrication of metallo-dielectric structures on the optical fiber tip by using a self-assembly technique. Our studies aim to attain advanced nanostructured sensors by exploiting easy and low-cost fabrication processes suitable to be employed in massive production of technologically advanced devices. The pursued approach basically consists in the preliminary preparation of a patterned polymeric film by the breath figure technique, directly on the optical fiber tip, and in the successive metal deposition by evaporation. The experimental results demonstrate the successful creation of a metallo-dielectric honeycomb pattern on the optical fiber tip. The sensing properties of the optical fiber probes have been successfully explored in terms of sensitivity to the surrounding refractive index changes demonstrating their potentialities for chemical and biological sensing applications.