Temperature effect under different parameters in CuInS2/ZnS core/shell quantum dot-doped liquid core optical fiber

We fabricated quantum dot (QD)-doped liquid core optical fibers (LCOFs) by doping CuInS2 (CIS) QDs and CuInS2/ZnS (CIS/ZnS) core/shell QDs with cladding times of 60, 70, 80, and 90 min. We compared and analyzed their emission spectral properties with increasing external temperature at different fiber diameters, fiber lengths, and doping concentrations, in addition to comparing them with CdSe/ZnS QD-doped LCOFs. As the temperature rises, the peak wavelength of the emission spectra of five QD-doped LCOFs shifts to long wavelengths and then to short, whereas the peak intensity decreases throughout the experiment. The emission intensity of the fiber doped with CIS/ZnS QD with a 60-min cladding time shows a greater decay trend with temperature, which has potential for temperature detection. The emission intensity of the fiber doped with CIS/ZnS QD with a 90-min cladding time decays slower with increasing temperature than that of CdSe/ZnS QDs, showing a stronger temperature stability. The smaller the fiber length, fiber diameter, and doping concentration, the more stable the emission, indicating a great significance to QD-based optical fiber amplifiers and lasers.