Random lasing carbon dot fibers for multilevel anti-counterfeiting

Random lasers, which achieve light amplification through random light scattering in disordered laser gain medium, have found widespread applications in varieties of areas due to the convenient design of laser cavities. In this work, carbon dot fibers with superior fluorescence stability under a high temperature or high humidity environment are fabricated by using a single-step partial thermal decomposition method. Random lasers, which are used for multilevel anti-counterfeiting, are achieved from different types of carbon dot fibers by 370 nm excitation at room temperature. Multilevel anti-counterfeiting is realized by tuning the lasing spectra (between similar to 428 and 560 nm) and threshold (between similar to 2 and 25 mJ cm(-2)) at designated decomposition times and fiber diameters. It is extremely difficult to counterfeit lasing spectra and the specific laser threshold simultaneously. As a result, this will comprehensively improve system safety.

Automated summary

Random lasers, achieved through random light scattering in disordered laser gain medium, have been widely utilized for various applications. This study successfully fabricated carbon dot fibers with superior fluorescence stability under harsh environmental conditions, and demonstrated multilevel anti-counterfeiting using these fibers as random lasers. By tuning the lasing spectra and threshold, system safety can be comprehensively enhanced.