Integrating aligned nanorod array onto optical fibers for SERS probes

Abstract

The use of fiber optics can greatly reduce device size while maintaining the sensitivity. Recently, nanostructures, especially metallic nanoparticles, have been incorporated into fiber optical sensors to obtain high sensitivity and specificity. Here, we propose a new way to integrate aligned nanorods onto optical fibers using a modified oblique angle deposition (OAD) technique. By rotating the optical fiber with a proper tilting angle, aligned nanorods from materials such as metals, semiconductors and metal oxides have been successfully deposited. With a slight modification, multilayer film/nanorod and nanorod/nanorod structures have also been demonstrated. This method has the advantage to coat aligned nanorods on optical fibers at low temperature, and is particularly promising for preparing nanostructured fiber optical probes for sensor applications. We also demonstrate that the optical fiber with its tip coated with Ag nanorod arrays can act as a Surface Enhance Raman Scattering (SERS) sensor.