Random lasing carbon dot fibers for multilevel anti-counterfeiting

Abstract

Random lasing is achieved from carbon dot fibers. Tunability of the lasing wavelength and threshold, which are key to achieving multilevel anti-counterfeiting, is realized by controlling the thermal decomposition time and fiber diameter.

Ultra‐Broadband Random Laser and White‐Light Emissive Carbon Dots/Crystal In‐Situ Hybrids

“…For the first time, the wavelength range of laser reaches 285 nm (315-600 nm) within an emission band of CDs-based materials, which is wider compared to reported works (Table S1, Supporting Information). [24,26,28,[44][45][46][47][48][49][50][51] Under ambient illumination, Et3BTC, SiCDs, and SiCDs/Et3BTC hybrids are white, brown, and light yellow, respectively. Under 365 nm UV lamp, SiCDs/Et3BTC hybrids and SiCDs exhibit cold white fluorescence, while Et3BTC shows no obvious fluorescence (upper right corner of Figure 1).…”

Tunable NIR Lasing in MOF for Multi‐Level Complex Photonic Barcodes

“…Optical Mater. 2023, 11,2202714 secret-related fields, they will be checked and compared with the references. For example, an ID-card (A) of unknown authenticity is circulated, temporarily named as ID-card (A?).…”

“…Such tags with low complexity and restricted capacity may be easily counterfeited by other materials with similar optical performances. [9][10][11][12] It is urgent to develop novel tags with the multi-level complexity. Especially, near-infrared (NIR) light is invisible but could be per-properties, resulting in controllable and dynamic barcodes.…”

Optofluidic devices with programmable and responsive functions

“…192,193,195,[238][239][240][241] By taking advantage of emission properties of luminescent materials, security labels with rapid readability and rich anticounterfeiting features have been proposed, including lasing signal, photonics barcodes, and luminescence images. 87,208,212,[242][243][244][245][246][247][248] To enhance the security level of optical encryption systems, multi-level optical security tags based on PL patterns have been developed to facilitate authentication. [249][250][251][252] For instance, security labels combining macroscopic patterns and microscale unclonable features have been proposed, where different scales would provide different information.…”

“…Besides inkjet printing, recent studies have also illustrated the potential of using fiber as an optical anticounterfeiting platform. 243,[266][267][268][269][270] By taking advantage of the high flexibility and extra compactness of fiber, 271 here an optofluidic fiber-based optical anticounterfeiting system is proposed by infiltrating randomly distributed dual-color microcavities into the three-channel suspended core optical fiber (TC-SCOF).…”