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101.
Mengjie Wei Arvydas Ruseckas Van T. N. Mai Atul Shukla Ilene Allison Shih-Chun Lo Ebinazar B. Namdas Graham A. Turnbull Ifor D. W. Samuel 《Laser u0026amp; Photonics Reviews》2021,15(8):2100028
Organic semiconductors possessing tightly bound Frenkel excitons are known to be attractive candidates for demonstrating polariton lasing at room temperature. As polariton lasing can occur without inversion, it is a potential route to very low threshold coherent light sources. However, so far, the thresholds of organic polariton lasers have generally been much higher than those of organic photon lasers. Here this problem has been addressed by investigating two new organic molecules with a structure combining fluorene and carbazole groups. The materials are readily deposited from solution and exhibit high photoluminescence quantum yields, high absorption coefficients, and large radiative decay rates in neat films. Room temperature polariton lasing is realized in both materials with incident thresholds of 13.5 and 9.7 µJ cm−2, corresponding to absorbed thresholds of 3.3 and 2.2 µJ cm−2, respectively. These are the lowest values reported to date for polariton lasing in organic semiconductor materials, and approach typical values for organic photon lasers. The step-like power dependent blue-shift of polariton modes indicates an interplay between different depletion channels of the exciton reservoir. This work brings practical room temperature polaritonic devices and future realization of electrically driven polariton lasers a step closer. 相似文献
102.
103.
104.
Ling Bai Yuheng He Jiajing Zhou Yun Lim Van Cuong Mai Yonghao Chen Shuai Hou Yue Zhao Jun Zhang Hongwei Duan 《Advanced Optical Materials》2019,7(13)
Amorphous photonic structures (APSs) with isotropic structural colors are of great promise for creating reflective full‐color displays or responsive colorimetric devices. However, there is a lack of guiding principles in developing stimuli‐responsive functional APSs, and the building blocks of APSs are still limited to spherical particles despite the increasing emergence of anisotropic functional particles. Moreover, current production of APSs, in particular high‐resolution APS patterns, is not fundamentally compatible with industrial manufacturing technologies, forming a major barrier toward their applications. Presented here is a proof‐of‐concept study on scalable fabrication of responsive APSs by colloidal assembly of spherical/polyhedral metal‐organic framework (MOF) particles on liquid‐permeable substrates. It is shown that infiltration assisted Mayer rod coating allows for rapid production of customized multicolored structural color patterns of MOF APSs by controlling liquid wetting/infiltration on the substrate with printed wax coatings. Small‐angle X‐ray scattering and optical measurements reveal the structural parameters of MOF APSs such as average nearest interscattering spacing and particle packing density, theoretically relating the optical properties and responsive color shifts of MOF APSs to factors affecting their scattering profile, which provides the guideline for the development of smart APS photonic devices via a wide spectrum of colloidal particles for diverse applications. 相似文献
105.
This paper reports a new Cartesian‐grid collocation method based on radial‐basis‐function networks (RBFNs) for numerically solving elliptic partial differential equations in irregular domains. The domain of interest is embedded in a Cartesian grid, and the governing equation is discretized by using a collocation approach. The new features here are (a) one‐dimensional integrated RBFNs are employed to represent the variable along each line of the grid, resulting in a significant improvement of computational efficiency, (b) the present method does not require complicated interpolation techniques for the treatment of Dirichlet boundary conditions in order to achieve a high level of accuracy, and (c) normal derivative boundary conditions are imposed by means of integration constants. The method is verified through the solution of second‐ and fourth‐order PDEs; accurate results and fast convergence rates are obtained. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007 相似文献
106.
The Bose-Einstein distribution is used to investigate Landau's hydrohynamical model with viscosity. In case the viscosity dependence on the temperature isT 3, the correction to the multiplicity behaves like 1/E and is found to be negligible for thepp data. A discussion is presented on a possibility of reconcilingE 1/2 and logE dependence of the multiplicity law. 相似文献
107.
芳香族共聚酯液晶的椭圆偏振光谱与光学性质的研究 总被引：1，自引：0，他引：1
应用自动化椭圆偏振光谱和紫外－可见光谱表征了两种芳香族共聚酯液晶的光学性质，发现由于分子结构和受激发电子振动跃迁的不同，使共聚酯液晶薄膜具有不同的折射率变化，产生不的同光学色散现象。 相似文献
108.
An efficient algorithm is developed for solving linear programs with an additional reverse convex constraint having a special structure. Computational results are presented and discussed. 相似文献
109.
Xinjian Yi Zhihong Mai Xinrong Zhao Fangqiao Zhou Luqin Liu 《International Journal of Infrared and Millimeter Waves》1996,17(4):705-710
8-element linear array IR detectors based on high Tc superconducting films have been fabricated. The thin films were deposited by magnetron sputtering onZrO
2 substrates and patterned by standard photolithographic technique forming microbridge structure. An average detectivity of 1.85 × 109
cmHz
1/2 W–1 with a variance of less than 20% in the detector-to-detector detectivity of the array has been obtained at the operating temperature of 84K. A bolometric response mechanism has been discussed. 相似文献
110.
For almost twenty years, the Ford-Johnson algorithm for sortingt items using comparisons was believed to be optimal. Recently, Manacher was able to show that the Ford-Johnson algorithm is not optimal for certain ranges of values oft. In this paper, we present some new algorithms which achieve much stronger results compared to Manacher's algorithms. 相似文献