A plasmonic D-shaped photonic crystal fiber (PCF) sensor for refractive index (RI) and temperature is designed and studied in this paper. The RI channel is made up of a silver thin layer deposited on the plane of the D-type structure, and the temperature sensing channel is formed by a silver nanowire and benzene filled in an elliptical hole in the PCF. The designed structure can be used for temperature and RI sensing via coupling between the core-guided modes and the surface plasmon modes around Ag nanowire and Ag thin layer. The coupling characteristic and sensing performance of the proposed dual-functional sensor is studied in the present work. Results show that the maximum sensitivity in terms of RI units (RIU) is 6.9 μm/RIU in the range of 1.33-1.38, and the maximum temperature sensitivity is 3 μm /°C in the range of 27 °C-67 °C.

A plasmonic D–shaped photonic crystal fiber (PCF) sensor for refractive index (RI) and temperature is designed and studied in this paper. The RI channel is made up of a silver thin layer deposited on the plane of the D–type structure, and the temperature sensing channel is formed by a silver nanowire and benzene filled in an elliptical hole in the PCF. The designed structure can be used for temperature and RI sensing via coupling between the core–guided modes and the surface plasmon modes around Ag nanowire and Ag thin layer. The coupling characteristic and sensing performance of the proposed dual–functional sensor is studied in the present work. Results show that the maximum sensitivity in terms of RI units (RIU) is 6.9 µm/RIU in the range of 1.33–1.38, and the maximum temperature sensitivity is 3 µm /°C in the range of 27°C–67°C.

In this article, we propose and study a D–shaped plasmonic refractive index (RI) sensor. The numerical simulation is performed by the finite–element method (FEM). Results indicate that the proposed RI sensor is particularly proper for sensing in the wavelength range of 0.5 to 0.7 μm. When the analyte RI varies from 1.33 to 1.36, the highest wavelength sensitivity of 9500 nm/RIU and RI resolution of 6.5 ×10–6 RIU are obtained. Besides, the highest amplitude sensitivity of 215 RIU–1 is achieved with a high linearity of 0.99862. These results confirm the capability of the proposed sensor for rapid and accurate detection of RI change in biological and industrial applications.