Abstract
In this paper, a nano-scale surface plasmon structure type temperature sensor was proposed. Through the theoretical analysis and numerical simulation, the temperature sensing characteristics of the system were studied. The nano temperature sensor consists of a metal-medium-metal structure SPPs waveguide and an ethanol-sealed rectangular cavity. The effects of electromagnetic wave transmission, field intensity distribution, temperature sensing characteristics and structural parameters on temperature sensitivity and coupling strength were studied. It was found that the effective refractive index of SPPs decreased linearly with the increase of temperature in the subwavelength structure of silver-ethanol-silver. The transmission spectrum of the temperature sensor has two transmission peaks at 600nm~1800nm, and the peak wavelength has blue shift with the increase of temperature. Further analysis shows that the peak wavelength of the transmission has a linear relationship with the temperature, and the ambient temperature can be detected by detecting the change of the formant. The results show that the sensitivity of the nanometer temperature sensor is related to the length of the rectangular cavity and the thermal coefficient of the liquid sealed in the nanometer rectangular cavity. The structure can obtain the temperature sensing sensitivity of -0.65nm/°C.
