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Jiahao Yan Dayu Zhu Yanjun Bao Qin Chen Baojun Li Wenshan Cai 《Laser \u0026amp; Photonics Reviews》2024,18(4):2300592
To achieve optoelectronic devices with high resolution and efficiency, there is a pressing need for optical structural units that possess an ultrasmall footprint yet exhibit strong controllability in both the frequency and spatial domains. For dielectric nanoparticles, the overlap of electric and magnetic dipole moments can scatter light completely forward or backward, which is called Kerker theory. This effect can expand to any multipoles and any directions, re-named as generalized Kerker effect, and realize controllable light manipulation at full space and full spectrum using well-designed dielectric structures. However, the complex situations of multipole couplings make it difficult to achieve structural design. Here, generative artificial intelligence (AI) is utilized to facilitate multi-objective-oriented structural design, wherein the study leverages the concept of “combined spectra” that consider both spectra and direction ratios as labels. The proposed generative adversarial network (GAN) is named as DDGAN (double-discriminator GAN) that discriminates both images and spectral labels. Using trained networks, the simultaneous design for scattering color and directivities, RGB color routers, as well as narrowband light routers is achieved. Notably, all generated structures possess a footprint <600 × 600 nm indicating their potential applications in optoelectronic devices with ultrahigh resolution. 相似文献
994.
色纯度改进的苯乙烯衍生物高效蓝色有机电致发光器件 总被引:6,自引:5,他引:1
以苯乙烯衍生物(amino-substituted distyryl arylene derivative,BCzVB)掺杂的4,4’-双(9-咔唑基)-1,1’-联苯(4,4’-N,N’-dicarbazole-biphyenyl,CBP)为发光层,制备了结构为ITO(indium tin oxide)/TPD(N,N’-diphenyl-N,N’-bis(3-methylphenyl)-1,1’biphenyl-4,4’diamine)/CBP:BCzVB/Alq3[tris-(8-hydroxy-quinolinato)aluminum)/Liq(8-hydroxy-quinolinato)lithium]/Al的电致发光器件。这里TPD、Alq3分别为空穴传输层和电子传输层,CBP:BCzVB为发光层,Liq为电子注入层。器件最高亮度为8500cd/m^2,效率为3.5cd/A(量子效率为2.6%),器件色坐标[Commission Internationale de l’Eclairage(CIE)CO-ordinates]为x=0.15,y=0.16,与纯BCzVB作发光层的器件相比,器件的发光色纯度和效率得到大幅提高。光致发光与电致发光对比分析表明器件的发光主要来自能量传递和陷阱俘获机制,但陷阱俘获机制起了主导作用。 相似文献
995.
A. P. Voitovich V. S. Kalinov N. N. Naumenko A. P. Stupak 《Journal of Applied Spectroscopy》2006,73(6):866-873
For radiation-induced intrinsic color centers, we show that the concentrations of identical centers and the concentration
ratios of different centers are quite different in the near-surface layer and within the interior volume of a lithium fluoride
crystal. We have established that these differences also depend on the sign of the difference between the temperature at which
the crystal was irradiated with γ photons and the vacancy mobility temperature. We provide an interpretation for the results
obtained, based on the structural features of the near-surface layer and the concentration ratio of vacancies and electrons
in the layer, serving as the starting components for color center formation. We found that the concentrations of centers change
over the course of a few days by tens of percent in the layer “emerging” from the interior onto the surface as a result of
cleavage of the crystal. We measured the luminescence lifetimes of F3 (R2) and F4 centers: 6.6 nsec and 11.7 nsec.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 6, pp. 775–781, November–December, 2006. 相似文献
996.
基于图论的图像分割算法的分析与研究 总被引:4,自引:1,他引:3
介绍了当前几种主要的基于图论的图像分割方法并加以比较.在已有算法的基础上,提出了几点重要改进用以解决白细胞分割的问题.实验中得到了比已有算法更接近人眼视觉的分割结果并大大减少了算法的运算量. 相似文献
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998.
Anne de Cuendias Emmanuel Ibarboure Sébastien Lecommandoux Eric Cloutet Henri Cramail 《Journal of polymer science. Part A, Polymer chemistry》2008,46(13):4602-4616
The purpose of this study is to correlate the nano‐organization in water of coil‐rod‐coil amphiphilic block copolymers constituted of a conjugated segment to their optoelectronic properties. The ABA block copolymer structures, easily achieved via coupling reactions, are based on conjugated rod of dihexylfluorene and 3,4‐ethylenedioxythiophene units linked to two flexible poly(ethylene oxide) or poly[(ethylene oxide)‐ran‐(propylene oxide)] chains. These well‐defined copolymers exhibited a range of specific morphologies in water, a good solvent of coil blocks and a bad solvent of the conjugated rod. Particularly, vesicles and micelles with spherical, cylindrical, or elongated shape were noticed. Correlations were attempted to be established between the weight percent of the conjugated sequence contained in the copolymers, the morphology of the nanostructures obtained by self‐assembly in solution and the resulting optical properties. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4602–4616, 2008 相似文献
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1000.
用新颖的线性三色采样中形光栅,可以在单色胶片上一步记录彩色图像,这种记录和再现过程不仅操作方便,仪器简单,经济,而且避免了色串扰,莫尔(Moire)条纹与分辨率的损失,消除了互调制,大大提高了光能利用率,本文给出了用计算机制作叶形光栅的方法,讨论了用这种光栅编码彩色图像的原理及其在全息照相和光学信息处理等其它方面潜在的应用。 相似文献