Highly Efficient D-type Photonic Crystal Fiber Surface Plasmon Resonance Sensor for Same Space–Time Temperature and Refractive Index Detection

Abstract

In order to realize temperature and refractive index (RI) detection of the analyte in the same space-time, a dual parameter detection photonic crystal fiber (PCF) optical sensor is proposed in this paper. Meanwhile, it can effectively avoid the interference of analyte temperature with RI detection. Further, a dual polished D-type structure is designed to provide mutually independent detection channels for temperature and RI, respectively. In addition, silver is used as the metal layer material, and polydimethylsiloxane (PDMS) and titanium dioxide (TiO2) are used as the temperature sensitive materials and RI sensitive materials, respectively. This structure design enables the two detection results to be output in parallel without interfering with each other. The proposed optical fiber sensor has a wide detection range and good detection performance. The temperature detection range can be as wide as -60°C to 100°C, and the RI detection range is 1.30-1.40. The best temperature resolution can be 1.42×10 -2 RIU, and the temperature wavelength sensitivity is 0.7 nm/°C. While the RI wavelength sensitivity is up to 1.25×10 4 nm/RIU, and the wavelength resolution is 8×10 -6 RIU.The detailed fabrication process of the sensor is given in this paper, as well as the practical application scenarios. Therefore, the optical fiber sensor proposed in this paper has research significance for the development of dual parameter detection optical fiber sensors.

SPR based dual parameter wide range curling pot shaped photonic crystal fiber sensor

“…The minimum resolution is usually based on the performance characteristics of the sensor and the measurement principle, and is the ratio of the minimum spectral resolution to the sensitivity, the minimum RI resolution and minimum temperature resolution of the sensor are respectively expressed by the following formula [14]:…”

“…Polydimethylsiloxane (PDMS) has a high negative thermo-optical coefficient of −4.5 × 10 −4 RIU °C−1 , good thermal conductivity, small viscosity change with temperature, and significant RI change with temperature. PDMS is used as a temperature-sensitive material to detect the change of ambient temperature through the movement of resonance wavelength [14], which can be used for a long time in the environment from −50 °C to 200 °C [3], at the same time, PDMS has good chemical stability [24], deformable and does not shrink [25], and can also isolate the reaction between gold film and the liquid to be measured to avoid oxidation of gold film. PDMS was solidified on a gold film close to core2 to detect temperature changes.…”