Highly sensitive surface plasmon resonance-based optical fiber multi-parameter sensor

摘要

We proposed and demonstrated a compact, simple-to-construct and highly sensitive optical fiber sensor capable of simultaneously measuring refractive index (RI) and temperature (T) based on surface plasmon resonance (SPR) effect. The device structure consists of a single mode fiber (SMF) spliced between two multimode fibers where whole SMF was coated with chromium and gold. The thicknesses of the layers of chromium and the gold were 5 nm and 30 nm, respectively. By covering half of the sensing region of the device with a polymer with high thermo-optic coefficient (TOC), it is feasible to detect RI and T changes with sensitives of 2664.540 nm/RIU and -2.852 nm/°C, respectively.