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941.
942.
943.
Fei Su Yaofeng Sun Cheng Yun Audrey Wong Hui Leong Ho Xiaoqi Chen 《Optics and Lasers in Engineering》2007,45(12):1177-1185
We have developed an integrated optical system to measure the warpage of a microdisplay product at post-packaging die-attach temperature and to test its hermeticity after manufacturing. This system is constructed based on the principle of Twyman/Green (T/G) interferometry and Newton interferometry. T/G interferometry is used to characterize warpage of the microdisplay's base-plate, while Newton interferometry is used to characterize the gap variance between face-plate and base-plate of the microdisplay. With these measurements, deformation and shape of the microdisplay can be comprehensively determined during its manufacturing process, which is critical for its quality test and reliability evaluation. Delicate mechanical system was designed to facilitate the optics integration and alignment. To evaluate the performance of the optical system itself, warpage of a sample was re-measured with Tailor–Hobson profilometer whose resolution is 10 nm, the results from these two testing systems agree well with each other. Some application examples of the integrated testing system were presented to verify its work efficiency. 相似文献
944.
Jue Wei Xiao-Feng Xu Yue Ding Zhi-Hui Kang Yun Jiang Jin-Yue Gao 《Optics and Lasers in Engineering》2007,45(3):419
A method employing an isosceles prism and a right-angle one is developed for loss measurement in planar waveguides. During the measuring process, the isosceles prism is fixed and the right-angle prism fixed on the waveguide slides by following the waveguide. Only by adjusting the gap thickness we can realize the loss measurement in planar waveguides. The method is demonstrated with an Ag/Na ion-exchanged waveguide fabricated on BK7 glass from AgNO3 melt diluted with NaNO3 (mass ratio 1:9), with the condition of 4 h and . The experimental results show that the method has the advantages on convenient operation, accurate results and no required end polishing. 相似文献
945.
In this paper, we investigate an inverse problem of recovering the zeroth-order coefficient and fractional order simultaneously in a time-fractional reaction-diffusion-wave equation by using boundary measurement data from both of uniqueness and numerical method. We prove the uniqueness of the considered inverse problem and the Lipschitz continuity of the forward operator. Then the inverse problem is formulated into a variational problem by the Tikhonov-type regularization. Based on the continuity of the forward operator, we prove that the minimizer of the Tikhonov-type functional exists and converges to the exact solution under an a priori choice of regularization parameter. The steepest descent method combined with Nesterov acceleration is adopted to solve the variational problem. Three numerical examples are presented to support the efficiency and rationality of our proposed method. 相似文献
946.
In this paper, the authors consider the range of a certain class of ASH algebras in [An, Q., Elliott, G. A., Li, Z. and Liu, Z., The classification of certain ASH C*-algebras of real rank zero, J. Topol. Anal., 14(1), 2022, 183–202], which is under the scheme of the Elliott program in the setting of real rank zero C*-algebras. As a reduction theorem, they prove that all these ASH algebras are still the AD algebras studied in [Dadarlat, M. and Loring, T. A., Classifying C*-algebras via ordered, m... 相似文献
947.
回生是淀粉加工、运输和储藏过程中的重要理化性质,快速检测淀粉回生程度对淀粉制品的品质和保质期有重要意义。为了探究二维相关光谱法(2D-COS)优选回生淀粉特征变量的可行性,研究结合2D-COS和光谱融合技术对小麦淀粉的回生特性进行定量表征。首先,将不同回生时间的小麦淀粉测定结晶度和回生度,从淀粉体系中晶体含量和对淀粉酶水解抗性的角度表征淀粉回生特性。然后,分别采集样品的近红外和中红外光谱数据,对采集的原始光谱进行Savitzky-Golay平滑和标准正态变量变换预处理后,结合偏最小二乘法分别基于近红外光谱、中红外光谱和融合光谱构建全光谱的预测模型。在此基础上,以回生天数为外部扰动,分别选取回生0, 1, 2, 3, 5, 7, 10, 14, 21和35 d的10条淀粉光谱进行2D-COS分析。通过分析同步谱和自相关谱,辨识了近红外13个和中红外11个与回生特性有关的特征波长。最后,基于这些特征波长进一步建立回生度和结晶度的预测模型。结果表明,全光谱模型结果中,光谱融合后的模型预测效果较好,结晶度模型的相对分析误差(RPD)值由1.203 4和2.069 0提高至3.980 9,回生度... 相似文献
948.
A hybrid cavity magnomechanical system to transfer the bipartite entanglements and achieve the strong microwave photon–phonon entanglement based on the reservoir engineering approach is constructed. The magnon mode is coupled to the microwave cavity mode via magnetic dipole interaction and to the phonon mode via magnetostrictive force (optomechanical-like). It is shown that the initial magnon-phonon entanglement can be transferred to the photon-phonon subspace in the case of these two interactions cooperating. In the reservoir-engineering parameter regime, the initial entanglement is directionally transferred to the photon-phonon subsystem, so a strong bipartite entanglement in which the magnon mode acts as the cold reservoir to effectively cool the Bogoliubov mode delocalized over the cavity and the mechanical deformation mode is obtained. Moreover, dual-mode cooling is realized by engineering the dissipation of photon and phonon modes within the target mode, which allows entanglement to be further enhanced. The results indicate that the steady-state entanglement is robust against temperature. The dual-mode cooling reservoir engineering scheme can potentially be extended to other three-mode quantum systems. 相似文献
949.
Shuang-Shuang Kong Wei-Kai Liu Xiao-Xia Yu Ya-Lin Li Liu-Zhu Yang Yun Ma Xiao-Yong Fang 《Frontiers of Physics》2023,18(4):43302
Silicon carbide nanosheets (SiCNSs) have a very broad application prospect in the field of new two-dimensional (2D) materials. In this paper, the interlayer interaction mechanism of bilayer SiCNSs (BL-SiCNSs) and its effect on optical properties are studied by first principles. Taking the charge and dipole moment of the layers as parameters, an interlayer coupling model is constructed which is more convenient to control the photoelectric properties. The results show that the stronger the interlayer coupling, the smaller the band gap of BL-SiCNSs. The interlayer coupling also changes the number of absorption peaks and causes the red or blue shift of absorption peaks. The strong interlayer coupling can produce obvious dispersion and regulate the optical transmission properties. The larger the interlayer distance, the smaller the permittivity in the vertical direction. However, the permittivity of the parallel direction is negative in the range of 150-300 nm, showing obvious metallicity. It is expected that the results will provide a meaningful theoretical basis for further study of SiCNSs optoelectronic devices. 相似文献
950.