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1.
Zhuo Shi Ningning Dong Dingfeng Zhang Xiaofang Jiang Guanxin Du Shichao Lv Jiejie Chen Jun Wang Shifeng Zhou 《Journal of the American Ceramic Society》2019,102(7):3965-3971
The construction of nonlinear optical materials featuring asymmetric transmission of light is of great technological importance for various applications, including optical switching and optical power limiting. A significant challenge is the scalable fabrication of material candidates with good photochemical stability, high optical transmittance, and excellent optical limiting performance. Here, we present a nanocrystallization avenue for constructing hybrid optical limiting materials that exhibit ultrafast and robust optical limiting performance. The experimental results show that the controllable relaxation of a niobate glass may lead to the clustering of Nb-O units and contracting of the bandgap. It results in the notable improvement in nonlinear optical properties, including the enhanced saturation irradiance (380 GW/cm2), doubly increased nonlinear coefficient, and decreased limiting threshold (200 GW/cm2). Our results suggest a promising material that exhibits promising applications for protecting eyes and sensitive components from laser-induced damage. 相似文献
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3.
双光子Jaynes-Cummings模型的亚泊松光子统计特性研究 总被引:4,自引:1,他引:3
本文利用量子电动力学理论和缀饰原于方法,对双光子James-Cummings模型中单模激光场的稳态亚泊松光子统计性质进行了系统研究。结果表明:激光上能级相对泵浦参量Xa具有一个确定的阈值Xat;当Xa>Xat时,光场呈现亚泊松光子统计;而当Xa>>Xat时,光场将呈现出深度且完全恒定的亚泊松光子统计。 相似文献
4.
Bianca Stoean Dumitrita Rugina Monica Focsan Ana-Maria Craciun MÎdÎlina Nistor Tamas Lovasz Alexandru Turza Ioan-Dan Porumb Emese Gl Castelia Cristea Luminita Silaghi-Dumitrescu Simion Astilean Luiza Ioana Gaina 《International journal of molecular sciences》2021,22(6)
We report here the synthesis and structural characterization of novel cationic (phenothiazinyl)vinyl-pyridinium (PVP) dyes, together with optical (absorption/emission) properties and their potential applicability as fluorescent labels. Convective heating, ultrasound irradiation and mechanochemical synthesis were considered as alternative synthetic methodologies proficient for overcoming drawbacks such as long reaction time, nonsatisfactory yields or solvent requirements in the synthesis of novel dye (E)-1-(3-chloropropyl)-4-(2-(10-methyl-10H-phenothiazin-3-yl)vinyl)pyridin-1-ium bromide 3d and its N-alkyl-2-methylpyridinium precursor 1c. The trans geometry of the newly synthesized (E)-4-(2-(7-bromo-10-ethyl-10H-phenothiazin-3-yl)vinyl)-1-methylpyridin-1-ium iodide 3b and (E)-1-methyl-4-(2-(10-methyl-10H-phenothiazin-3-yl)vinyl)pyridin-1-ium tetrafluoroborate 3a′ was confirmed by single crystal X-ray diffraction. A negative solvatochromism of the dyes in polar solvents was highlighted by UV-Vis spectroscopy and explanatory insights were supported by molecular modeling which suggested a better stabilization of the lowest unoccupied molecular orbitals (LUMO). The photostability of the dye 3b was investigated by irradiation at 365 nm in different solvents, while the steady-state and time-resolved fluorescence properties of dye 3b and 3a′ in solid state were evaluated under one-photon excitation at 485 nm. The in vitro cytotoxicity of the new PVP dyes on B16-F10 melanoma cells was evaluated by WST-1 assay, while their intracellular localization was assessed by epi-fluorescence conventional microscopy imaging as well as one- and two-photon excited confocal fluorescence lifetime imaging microscopy (FLIM). PVP dyes displayed low cytotoxicity, good internalization inside melanoma cells and intense fluorescence emission inside the B16-F10 murine melanoma cells, making them suitable staining agents for imaging applications. 相似文献
5.
双光子加工技术需要通过数据准备软件将CAD模型转换为加工数据.为此提出了三种进行双光子加工的数据准备方法,即STL处理、图片处理和线条处理;基于MFC的单文档/视图结构框架开发了软件.应用实例表明,该软件界面友好、运行可靠. 相似文献
6.
双光子吸收材料在诸多领域如光限幅、双光子上转换激射、双光子荧光显微术、三维光存储以及三维微加工等方面有潜在的应用前景.近年来,对有机双光子吸收材料的研究正成为材料领域研究的热点之一.杂环化合物由于具有优良的双光子性质,高的光学稳定性,因而成为研究的重点.对杂环简单的化学修饰,就可以实现对材料的最大吸收波长和发射波长大范围的调节.同时杂环化合物一般具有较强的推拉电子能力,能有效的提高双光子上转换激射效率,是一类很有发展潜力的双光子材料. 相似文献
7.
为进行双光子荧光显微成像研究,搭建了一套飞秒激光光源双光子荧光显微成像系统.对超短脉冲锁模激光器的成像优势、双光子激励饱和功率及系统分辨率进行了理论推导,利用飞秒激光器、显微镜、数据采集设备与控制装置及扫描控制软件搭建了显微成像系统,并对Rhodamine B样品进行双光子荧光显微成像实验.结果表明:相同条件下,超短脉冲锁模激光器的双光子荧光产率为连续光输出激光器的105倍;采用UPLSAPO60XO型物镜时,双光子激励饱和功率为50 m W,理论横向和轴向分辨率为303 nm与727 nm;该系统具有显微成像能力,且实际横向分辨率小于3μm. 相似文献
8.
Coralie Greant Bo Van Durme Jasper Van Hoorick Sandra Van Vlierberghe 《Advanced functional materials》2023,33(39):2212641
Multiphoton lithography (MPL) is a powerful and useful structuring tool capable of generating 2D and 3D arbitrary micro- and nanometer features of various materials with high spatial resolution down to nm-scale. This technology has received tremendous interest in tissue engineering and medical device manufacturing, due to its ability to print sophisticated structures, which is difficult to achieve through traditional printing methods. Thorough consideration of two-photon photoinitiators (PIs) and photoreactive biomaterials is key to the fabrication of such complex 3D micro- and nanostructures. In the current review, different types of two-photon PIs are discussed for their use in biomedical applications. Next, an overview of biomaterials (both natural and synthetic polymers) along with their crosslinking mechanisms is provided. Finally, biomedical applications exploiting MPL are presented, including photocleaving and photopatterning strategies, biomedical devices, tissue engineering, organoids, organ-on-chip, and photodynamic therapy. This review offers a helicopter view on the use of MPL technology in the biomedical field and defines the necessary considerations toward selection or design of PIs and photoreactive biomaterials to serve a multitude of biomedical applications. 相似文献
9.
Antonio Balena Marco Bianco Ferruccio Pisanello Massimo De Vittorio 《Advanced functional materials》2023,33(39):2211773
Two-Photon Lithography, thanks to its very high sub-diffraction resolution, has become the lithographic technique par excellence in applications requiring small feature sizes and complex 3D pattering. Despite this, the fabrication times required for extended structures remain much longer than those of other competing techniques (UV mask lithography, nanoimprinting, etc.). Its low throughput prevents its wide adoption in industrial applications. To increase it, over the years different solutions have been proposed, although their usage is difficult to generalize and may be limited depending on the specific application. A promising strategy to further increase the throughput of Two-Photon Lithography, opening a concrete window for its adoption in industry, lies in its combination with holography approaches: in this way it is possible to generate dozens of foci from a single laser beam, thus parallelizing the fabrication of periodic structures, or to engineer the intensity distribution on the writing plane in a complex way, obtaining 3D microstructures with a single exposure. Here, the fundamental concepts behind high-speed Two-Photon Lithography and its combination with holography are discussed, and the literary production of recent years that exploits such techniques is reviewed, and contextualized according to the topic covered. 相似文献
10.