Fabry-Perot type sensor with surface plasmon resonance

摘要

The main point of this letter concerns the fabrication of an optical sensor with improved sensitivity for detecting molecular adsorption onto a gold surface. The sensor consists of a Fabry-Perot interferometer whose one of two reflective layers is constituted by an island-type gold film having a pronounced local surface plasmon resonance. The results presented in the letter show that the binding of molecules on the device surface induces a differential interference pattern whose amplitude is increased by the plasmon resonance. The sensor sensitivity can be improved by further deposition of Au nanoparticles on the reflective layer. This kind of sensor has potential advantages since it is easy to fabricate and use and it possesses a submonolayer sensitivity.