Transparent glassy composites incorporating lead-free anti-perovskite halide nanocrystals enable tunable emission and ultrastable X-ray imaging

Lead halide perovskite materials exhibit excellent scintillation performance,which,however,suffer from serious stability and toxicity problems.In contrast,the heavy metal-free anti-perovskite materials[MX_(4)]XA_(3)(A=alkali metal;M=transition metal;X=Cl,Br,I),a class of electron-inverted perovskite derivatives,exhibit robust structural and photophysical stability.Here,we design and prepare a lead-free[MnBr_(4)]BrCs_(3) anti-perovskite nanocrystal(NC)-embedded glass for efficient X-ray-excited luminescence with high-resolution X-ray imaging with a spatial resolution of 19.1 Ip mm^(-1).Due to the unique crystal structure and the protection of the glass matrix,the Cs_(3)MnBr_(5) NC-embedded glass exhibits excellent X-ray irradiation stability,thermal stability,and water resistance.These merits enable the demonstration of real-time and durable X-ray radiography based on the developed glassy composite.This work could stimulate the research and development of novel metal halide anti-perovskite materials and open a new path for future development in the field of high-resolution and ultrastable X-ray imaging.

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.The color of tungsten phosphate glass doped with rare earth ions change reversibly from light yellow to blue upon alternating 473 nm laser illumination and temperature stimulation,resulting in the reversible luminescence modulation.The information data could be repeatedly written and erased in arbitrary 3D space of transparent glass,not only showing the ability of the excellent reproducibility and storage capacity,but also opening opportunities in information security.The present work expands the application fields of luminescent glass,and it is conducive to develop a novel 3D data storage and information encryption media.

飞秒激光辐照诱导光致变色玻璃中的上转换发光可逆调控和3D光学信息存储

快速响应、高发光对比度、三维存储和信息无损读取是光致变色材料光存储应用的几个关键因素.具有多光子非线性吸收的飞秒激光直写技术以其加工速度快、加工精度高等独特优势,正成为玻璃三维空间微加工功能单元的有效工具.本工作研究了800 nm飞秒激光照射下稀土离子掺杂透明玻璃的光致变色性质,结果证实在800 nm飞秒激光辐照下玻璃展现了快速光致变色响应.在光致变色玻璃中实现了92%的上转换发光调控.光致变色玻璃可通过热刺激漂白回原色,在800 nm飞秒激光辐照和热处理交替刺激下,光致变色玻璃的透射率和上转换调控表现出良好的重现性.通过800 nm飞秒激光照射,可将数据信息写入透明玻璃内部,实现三维信息存储.结果表明,800 nm飞秒激光辐照诱导的光致变色玻璃是理想的光学数据存储介质.

PbS quantum dots and Ba F_(2):Tm^(3+) nanocrystals co-doped glass for ultra-broadband near-infrared emission [Invited]

With the rapid growth of optical communications traffic,the demand for broadband optical amplifiers continues to increase.It is necessary to develop a gain medium that covers more optical communication bands.We precipitated PbS quantum dots(QDs) and Ba F_(2):Tm^(3+) nanocrystals (NCs) in the same glass to form two independent emission centers.The Ba F_(2)NCs in the glass can provide a crystal field environment with low phonon energy for rare earth (RE) ions and prevent the energy transfer between RE ions and PbS QDs.By adjusting the heat treatment schedule,the emission of the two luminescence centers from PbS QDs and Tm^(3+) ions perfectly splices and covers the ultra-broadband near-infrared emission from 1200 nm to 2000 nm with bandwidth over 430 nm.Therefore,it is expected to be a promising broadband gain medium for fiber amplifiers.

钙钛矿的恢复

Recently,metal halide perovskite(MHP)materials have achieved a huge breakthrough in photovoltaic and optoelectronic devices due to their high power conversion efficiency,high photoluminescence(PL)quantum yield,and simple,cost-effective preparation.Within a short period,perovskite-based solar cells achieve power conversion efficiency exceeding 25%[1,2],while perovskite-LEDs obtain external quantum efficiency over 21%[3].Nevertheless,the long-term stability of MHP materials and devices is a critical barrier to commercial applications[4].

Reply to Comment on"Reversible 3D optical data storage and information encryption in photomodulated transparent glass medium

Dear Editor,Tungsten-based photochromic materials are well known,suchastungsten-phosphateglasses,tungsten-telluriteglasses,andtungsten-borateglasses'.Photoluminescence glasses exhibit a wide range of application in the fields of display,lighting,laser and optical thermometry,et al.Combination of photochromic and luminescence can extend the application of luminescence materials2-7.Our focus is not on the development of new photochromic materials,but on the control of luminescence through photochromic reaction,especially achieved the real complex threedimensional patterns using laser directly writing technology in photo-modulated transparent glass.In our work2,the three-dimensional optical data storage and information encryption application of photochromic glass with luminescence was obtained.