The Experts below are selected from a list of 10767 Experts worldwide ranked by ideXlab platform
Wenbin Xu - One of the best experts on this subject based on the ideXlab platform.
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Ultra-Compact Waveguide-Integrated TE-Mode Converters With High Mode Purity by Designing Ge/Si Patterns
IEEE Photonics Journal, 2019Co-Authors: Han Ye, Zhongyuan Yu, Fengyi Yu, Jing Li, Bida Su, Wenbin XuAbstract:In this letter, we propose ultra-compact TE-polarized even-to-odd mode converter designs by introducing Ge/Si patterns into silicon waveguide-integrated Functional Region. The Ge areas with continuous boundaries are determined by topology optimization that combines finite element method, geometric projection method, and method of moving asymptotes. Both two-dimensional (2D) and quasi-3D designs are presented. Simultaneous beam splitting and phase shifting are achieved in the Functional Region with only 1.0 × 1.55 μm2 area. Based on the 3D finite-difference time-domain simulations, the quasi3D designs possess satisfactory mode purity (>0.99) at center wavelength 1550 nm, and the mode purity keeps higher than 0.92 within the wavelength range from 1500 to 1600 nm. Meanwhile, the forward transmission efficiency is shown higher than 0.89 within the operational bandwidth. Moreover, the robustness is demonstrated by considering the loss of Ge material and the geometric deviations. The proposed mode-order converters bring together advantages including wavelength footprint, high mode purity, low insertion loss, and large operational bandwidth.
Han Ye - One of the best experts on this subject based on the ideXlab platform.
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Ultra-Compact Waveguide-Integrated TE-Mode Converters With High Mode Purity by Designing Ge/Si Patterns
IEEE Photonics Journal, 2019Co-Authors: Han Ye, Zhongyuan Yu, Fengyi Yu, Jing Li, Bida Su, Wenbin XuAbstract:In this letter, we propose ultra-compact TE-polarized even-to-odd mode converter designs by introducing Ge/Si patterns into silicon waveguide-integrated Functional Region. The Ge areas with continuous boundaries are determined by topology optimization that combines finite element method, geometric projection method, and method of moving asymptotes. Both two-dimensional (2D) and quasi-3D designs are presented. Simultaneous beam splitting and phase shifting are achieved in the Functional Region with only 1.0 × 1.55 μm2 area. Based on the 3D finite-difference time-domain simulations, the quasi3D designs possess satisfactory mode purity (>0.99) at center wavelength 1550 nm, and the mode purity keeps higher than 0.92 within the wavelength range from 1500 to 1600 nm. Meanwhile, the forward transmission efficiency is shown higher than 0.89 within the operational bandwidth. Moreover, the robustness is demonstrated by considering the loss of Ge material and the geometric deviations. The proposed mode-order converters bring together advantages including wavelength footprint, high mode purity, low insertion loss, and large operational bandwidth.
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Ultra-compact broadband mode converter and optical diode based on linear rod-type photonic crystal waveguide.
Optics Express, 2015Co-Authors: Han Ye, Dong-lin Wang, Zhongyuan Yu, Jinqiannan Zhang, Zhi-hui ChenAbstract:In this paper, we present extremely compact designs of both broadband mode converter and optical diode in linear rod-type photonic crystal (PhC) waveguide with Functional Region consisting of only 4 × 1 unit cells of perfect PhC. The dielectric distribution inside Functional Region are optimized by combining geometry projection method and method of moving asymptotes. Bidirectional mode converter realizes above 60% transmission efficiency within bandwidth 0.02c/a, where c and a represent light velocity and PhC lattice constant respectively. Optical diode achieves above 19 dB unidirectionality for even mode within bandwidth 0.01c/a. Moreover, the proposed designs have reasonable tolerance of rod boundary fluctuation. We expect the results will help developing recipes for future PhC devices in all-optical integrated circuits.
Zhongyuan Yu - One of the best experts on this subject based on the ideXlab platform.
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Ultra-Compact Waveguide-Integrated TE-Mode Converters With High Mode Purity by Designing Ge/Si Patterns
IEEE Photonics Journal, 2019Co-Authors: Han Ye, Zhongyuan Yu, Fengyi Yu, Jing Li, Bida Su, Wenbin XuAbstract:In this letter, we propose ultra-compact TE-polarized even-to-odd mode converter designs by introducing Ge/Si patterns into silicon waveguide-integrated Functional Region. The Ge areas with continuous boundaries are determined by topology optimization that combines finite element method, geometric projection method, and method of moving asymptotes. Both two-dimensional (2D) and quasi-3D designs are presented. Simultaneous beam splitting and phase shifting are achieved in the Functional Region with only 1.0 × 1.55 μm2 area. Based on the 3D finite-difference time-domain simulations, the quasi3D designs possess satisfactory mode purity (>0.99) at center wavelength 1550 nm, and the mode purity keeps higher than 0.92 within the wavelength range from 1500 to 1600 nm. Meanwhile, the forward transmission efficiency is shown higher than 0.89 within the operational bandwidth. Moreover, the robustness is demonstrated by considering the loss of Ge material and the geometric deviations. The proposed mode-order converters bring together advantages including wavelength footprint, high mode purity, low insertion loss, and large operational bandwidth.
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Ultra-compact broadband mode converter and optical diode based on linear rod-type photonic crystal waveguide.
Optics Express, 2015Co-Authors: Han Ye, Dong-lin Wang, Zhongyuan Yu, Jinqiannan Zhang, Zhi-hui ChenAbstract:In this paper, we present extremely compact designs of both broadband mode converter and optical diode in linear rod-type photonic crystal (PhC) waveguide with Functional Region consisting of only 4 × 1 unit cells of perfect PhC. The dielectric distribution inside Functional Region are optimized by combining geometry projection method and method of moving asymptotes. Bidirectional mode converter realizes above 60% transmission efficiency within bandwidth 0.02c/a, where c and a represent light velocity and PhC lattice constant respectively. Optical diode achieves above 19 dB unidirectionality for even mode within bandwidth 0.01c/a. Moreover, the proposed designs have reasonable tolerance of rod boundary fluctuation. We expect the results will help developing recipes for future PhC devices in all-optical integrated circuits.
Duan Wenbiao - One of the best experts on this subject based on the ideXlab platform.
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Notice of Retraction Heavy Metal Contamination of Soils and Its Evaluation in Different Greenbelt Functional Region of Harbin, China
2011 5th International Conference on Bioinformatics and Biomedical Engineering, 2011Co-Authors: Chen Lixin, Duan WenbiaoAbstract:The status of soil heavy metals (Cd, Hg, Pb and Cr) contamination in different greenbelt Functional Region of Harbin was investigated and evaluated. Their contamination sources were analysed. The results showed that the greenbelt soils in Harbin were contaminated to different degree by the four heavy metals stated above. The most heavy contaminant was Hg and its contamination reached heavy degree, the much heavy contaminants were Pb and Cd, Cr contamination was relatively mild; The contamination status was different in different greenbelt Functional Region, Cd and Hg contamination in the public greenbelt and Pb contamination in the road and traffic greenbelt were more heavy, Cr content in the suburban agricultural zone was comparatively higher; The decreasing ranking order of contamination degree was the public greenbelt, the habitation greenbelt, the road and traffic greenbelt, the suburban agricultural zone and productive greenbelt by method of fuzzy comprehensive assessment. Hg contamination in the public greenbelt mainly came from the atmospheric depositions of factories and traffic exhaust in Harbin, while fluorescent lamp was one of mercury pollution sources.
Wenbiao Duan - One of the best experts on this subject based on the ideXlab platform.
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Notice of Retraction: Heavy Metal Contamination of Soils and Its Evaluation in Different Greenbelt Functional Region of Harbin, China
2011 5th International Conference on Bioinformatics and Biomedical Engineering, 2011Co-Authors: Lixin Chen, Wenbiao DuanAbstract:This article has been retracted by the publisher.
