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Perovskite CsPbX3 (X = Cl, Br, I) nanocrystals with advantages of high quantum yield, narrow emission peaks, and tunable fluorescence are considered as the next generation of light‐emitting sources. However, fluorescence degradation due to the poor stability of perovskite nanocrystals in moisture, high temperature, and illumination remains one of the greatest challenges in their further development. In this work, a fully dense coating strategy is proposed to improve the overall stability of perovskite nanocrystals, especially under high‐density laser irradiation. A mesoporous silica SiO2 layer is introduced to construct a stable coating for isolating the perovskite from external environment. To eliminate the pores of the CsPbX3@SiO2, an inorganic glass is also employed via solution‐combustion technique to generate a fully compact encapsulation for further stability promotion. The as‐prepared nanocrystal‐in‐glass composite exhibits efficient and stable fluorescence performance in luminous efficiency, chromaticity, and long‐term reliability in the conditions of thermal shock, humidity, and blue laser irradiation. With the integration of red/green/blue emitting nanocrystals, the color gamut of the white laser lighting source covers 134% of the National Television Standards Committee standard, providing exciting opportunity for high performance laser‐driven white light generation. [ABSTRACT FROM AUTHOR]

Conventional near-infrared luminescent phosphors activated by transition metal elements or rare earth activators were already widely reported. In this work, we develop a self-activated near-infrared luminescent phosphor with a typical double perovskite structure, which exhibits an emission at 650–750 nm under excitation at 365 nm. The origin of the desired luminescence in (Ca,Sr)LaMgTaO 6 compounds is attributed to the oxygen vacancies defects, oxygen interstitial defects and substitution defects and antioccupation defects. Thermal quenching of photoluminescence is undesirable with an integrated emission loss of 30–50% at 150 °C, which needs to be improved. This new series of near-infrared luminescent materials have potential applications in agricultural cultivations and bio-imaging materials. More importantly, we demonstrate a strategy by self-activation to realize near-infrared light. [ABSTRACT FROM AUTHOR]

The pursuit of high‐resolution and advanced anti‐forgery technology has stimulated a growing demand for anti‐counterfeiting and encryption strategies with real‐time response and high security. Polarized patterns taking the advantage of high security, rapid response, simple operation, and great selectivity enable real‐time and non‐invasive detection by monitoring in different polarization directions. Here, a new strategy to design and fabricate the polarized CsPbBr3 quantum dot (QD) line arrays by femtosecond (fs) laser writing in a transparent glass matrix is proposed. The obtained line array structures endow isotropic CsPbBr3 QDs with macroscopic polarized emission with a polarization degree up to 0.189. Through programable design, the authors have created 2D and 3D polarized luminescent patterns made up of vertical and horizontal lines inside the glass for polarization‐sensitive optical anti‐counterfeiting patterns. The CsPbBr3 QD line arrays used in anti‐counterfeiting can be well maintained in the water environment. The successful demonstration of the laser writing CsPbBr3 QD polarization structures in glass highlights the versatility of anti‐counterfeiting and encryption. [ABSTRACT FROM AUTHOR]