Ultracompact Temperature-Compensated All-Fiber Ultraviolet Sensor Based on CdZnSe/ZnSe/ZnS Quantum Dots Sealed in Liquid Cavity

An ultracompact temperature-compensated all-fiber ultraviolet (UV) sensor based on CdZnSe/ZnSe/ZnS quantum dots (QDs) sealed in a liquid cavity is proposed. The UV-sensitive region is integrated inside the fiber to avoid interference from external media, and high fluorescence conversion efficiency and ultracompact structure are achieved due to the high fluorescence quantum efficiency and excellent luminescence stability of CdZnSe/ZnSe/ZnS QDs solution. The temperature crosstalk problem of semiconductor materials applied to sensors is solved in this single structure by monitoring of peak wavelength and intensity of fluorescence spectra simultaneously to achieve the temperature compensation function of the sensor. The results show a linear dependence of UV sensitivity on temperature, which can be demodulated through peak wavelength individually. In addition, the QDs sealed in a liquid cavity protected by hollow core fiber (HCF) can resist corrosion, high pressure, and electromagnetic interference, providing a new idea for UV detection in harsh environments.