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

Abstract

Developing functional photonic tags is of great importance to meet the globally increasing demand for information security and anti‐counterfeiting. However, it still suffers from the restricted encoding capacity, low complexity, and unsatisfactory confidentiality. Herein, a strategy is demonstrated to construct multi‐level complex photonic barcodes in near‐infrared (NIR) region based on a composition‐graded metal‐organic framework (MOF) heterostructure with the hierarchical encapsulation of different dye molecules. Such MOF microstructure exhibits switchable dual‐wavelength NIR lasing by adjusting the excited position, polarization direction, and pump energy. Thus, through converting the laser spectra with dynamic and regular changes to solid bars, the multi‐block photonic barcodes with three‐level encoding system are constructed, dramatically increasing the complexity and capacity. It makes the MOF‐based heterostructure with switchable lasing properties become a hard‐to‐counterfeit potential material for advanced anticounterfeiting of high‐level security.

Dynamically responsive photonic metal–organic frameworks

“…On the basis of this excited position-dependent two-photon polarized lasing in NIR region, an extension work is carried out. Similarly, LDS-798@LDS-722@ZJU-67 heterostructure (LDS-798, 4-[4-[4-(dimethylamino)phenyl]-1,3-butadienyl]-1-ethyl quinolinium perchlorate) was constructed and used for three-level photonic encoding based on the switchable dual-wavelength NIR lasing 140 . It increases the complexity and security of photonic tags, making the MOF-based heterostructure promising for advanced anticounterfeiting and information encryption in the future.…”

Guest Encapsulation in Metal–Organic Frameworks for Photonics

“…(e) Polarization directions-dependent emission spectra and the corresponding barcodes from ZJU-67⊃LDS-798+LDS-722 heterostructure. Reproduced with permission from ref . Copyright 2023 Wiley-VCH.…”

“…Similarly, based on this excited position dependent two-photon polarized lasing in NIR region, a two dyes-encapsulated ZJU-67⊃LDS-798+LDS-722 MOF heterostructure was built and exploited for three-level (excited position, polarization direction and pump energy) photonic encoding based on the switchable dual-wavelength NIR polarized lasing (Figure 9d,e). 53 It makes photonic tags more complex and secure, making the MOF-based heterostructure attractive for advanced anticounterfeiting and information encryption in the future. In addition to using MOF heterostructures to design laser switches and information encryption materials, our group also designed novel sandwich-like MOF-based mixed-matrix membranes (MMMs) to realize a high contrast (≈ 6.1 × 10 4 ) polarized laser switch by simultaneously controlling the UV irradiation and the polarization direction.…”

“…Such constructing strategies offer hybrid ZJU-68 heterostructures with unique advantages, such as the spatially segmented assembled and tightly confined linear dyes in the channels of ZJU-68 that efficiently minimize the intermolecular EnT originating from spectral overlap of the different wavelength dyes, avoiding signal cross-contamination. Similarly, based on this excited position dependent two-photon polarized lasing in NIR region, a two dyes-encapsulated ZJU-67⊃LDS-798+LDS-722 MOF heterostructure was built and exploited for three-level (excited position, polarization direction and pump energy) photonic encoding based on the switchable dual-wavelength NIR polarized lasing (Figure d,e) . It makes photonic tags more complex and secure, making the MOF-based heterostructure attractive for advanced anticounterfeiting and information encryption in the future.…”

Real-data-driven Real-time Reconfigurable Microwave Reflective Surface

“…One special advantage of a pure NN-driven scheme, compared to conventional optimization methods, is that no iterative process is involved in the prediction phase, which is crucial for an on-site system in need of fast response. This feature has been exploited recently to facilitate an emerging concept -the intelligent metasurface, which refers to metasurfaces that tune themselves in an adaptive manner, with little human intervention [22], from beam-forming [23], to sensing purposes [24,25]. In theory, similar strategy can be used for curved surfaces, and preliminary studies on NN-driven non-planer surface has been reported for cloaking or "illusion" applications [26][27][28], yet a more universal and versatile scheme is still needed for the surface to dynamically operate under different types of tasks.…”