Scintillating Glass Fiber Arrays Enable Remote Radiation Detection and Pixelated Imaging.

The emerging metal halide perovskites are challenging the traditional scintillators in the field of radiation detection and radiography. However, they lack the capability for remote and real-time radiation monitoring and imaging in confined and hostile conditions. To address this issue, details on an inorganic scintillating glass fiber incorporating perovskite quantum dots (QDs) as highly efficient pixelated radiation emitters are reported, while the glass fibers themselves serve at the same time as low-loss waveguides, enabling long-distance and underwater X-ray detection.

Boosted Second Harmonic Generation and Cascaded Sum Frequency Generation from a Surface Crystallized Glass Ceramic Microcavity.

The development of novel materials and structures for efficient second-order nonlinear micro/nano devices remains a significant challenge. In this study, the remarkable enhancement of second-harmonic generation (SHG) and cascaded sum frequency generation in whispering gallery mode microspheres made of surface-crystallized glass with a 6-µm BaTiSiO crystal layer are demonstrated. Attributed to the core-shell design, the BaTiSiO located on the surface can be efficiently coupled with whispering gallery modes, resulting in a highly efficient micron-scale cavity-enhanced second-order optical nonlinearity.

Reversible Growth of Halide Perovskites via Lead Oxide Hydroxide Nitrates Anchored Zeolitic Imidazolate Frameworks for Information Encryption and Decryption.

The low formation energies of metal halide perovskites endow them with potential luminescent materials for applications in information encryption and decryption. However, reversible encryption and decryption are greatly hindered by the difficulty in robustly integrating perovskite ingredients into carrier materials. Here, we report an effective strategy to realize information encryption and decryption by reversible synthesis of halide perovskites, on the lead oxide hydroxide nitrates (PbO(OH)(NO)) anchored zeolitic imidazolate framework composites.

Coupling Localized Laser Writing and Nonlocal Recrystallization in Perovskite Crystals for Reversible Multidimensional Optical Encryption.

The ability to generate and manipulate photoluminescence (PL) with high spatial resolution has been of primary importance for applications in micro-optoelectronics, while the emerging metal halide perovskites offer novel material platforms where diverse photonic functionalities and fine structuring are constantly explored. Herein, micro-PL patterns consisting of highly luminescent CsPbBr nanocrystals (NCs) in nonluminescent perovskite crystals are directly fabricated by focused femtosecond laser irradiation. Further modulation with a moisture field leads to the selective dissolution of the laser-destabilized perovskite structures as revealed by density functional theory simulations, thus allowing for facile control of the reversible PL from the recrystallization of moisture-induced CsPbBr NCs.

Reversible 3D optical data storage and information encryption in photo-modulated transparent glass medium.

Transparent glass has been identified as a vital medium for three-dimensional (3D) optical information storage and multi-level encryption. However, it has remained a challenge for directly writing 3D patterning inside a transparent glass using semiconductor blue laser instead of high-cost femtosecond laser. Here, we demonstrate that rare earth ions doped transparent glass can be used as 3D optical information storage and data encryption medium based on their reversible transmittance and photoluminescence manipulation.

Three-Dimensional Laser-Assisted Patterning of Blue-Emissive Metal Halide Perovskite Nanocrystals inside a Glass with Switchable Photoluminescence.

The high-precision patterning of metal halide perovskites (MHPs) is of paramount importance for their device application. Here, we demonstrate the femtosecond (fs)-laser-assisted formation of three-dimensional MHP nanocrystal (NC) patterns with strong blue photoluminescence (PL) inside an oxide glass. Our strategy enables the crystallization and erasing of CsPb(Cl/Br) NCs inside a glass localized around the laser focal area through a combination of fs laser irradiation and thermal treatment processes.

Anisotropic Excitation Polarization Response from a Single White Light-Emitting β-NaYF :Yb ,Pr Microcrystal.

Precise knowledge about optical and structural performance of individual rare earth (RE)-doped particles is extremely important for the optimization of luminescent particles and for fully exploiting their capability as multifunctional probes for interdisciplinary applications. In this work, optical and structural anisotropy of individual particles through RE-doped single fluoride microcrystals with controllable morphology is reported. Unique luminescent phenomena, for example, white light-emission from Pr at single particle level and different photoluminescent spectra variation dependence on excitation polarization orientation at different excitation direction are observed upon excitation with a 980 nm linearly polarized laser.

Formation, element-migration and broadband luminescence in quantum dot-doped glass fibers.

All solid-state PbS quantum dot (QD)-doped glass precursor fibers avoiding crystallization during fiber-drawing process are successfully fabricated by melt-in-tube technique. By subsequent heat treatment schedule, controllable crystallization of PbS QDs can be obtained in the glass precursor fibers, contributing to broad near-infrared emissions from PbS QD-doped glass fibers. Nevertheless, we find that element-migration and volatilization of sulfur simultaneously happen during the whole fiber-drawing process, because of the huge difference between the melting temperature of core glass and the fiber-drawing temperature.