The Experts below are selected from a list of 90585 Experts worldwide ranked by ideXlab platform
Anand Asundi - One of the best experts on this subject based on the ideXlab platform.
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Further study of Coupling Efficiency of ultra-small gradient-index fiber probe
Optik, 2019Co-Authors: Chi Wang, Jianmei Sun, Bin Kuang, Zhuli Wen, Anand AsundiAbstract:Abstract In this paper, the relationship between the Coupling Efficiency and transmission distance of different fiber optic probes is compared for further studying the focusing performance of ultra-small GRIN fiber probes. Taking an example of five typical ultra-small GRIN fiber probes such as single mode fiber (SMF), "SMF + 0.31mm 50/125 GRIN", "SMF + 0.36mm NCF + 0.12mm 50/125 GRIN", "SMF + 0.48mm 100/140 GRIN", "SMF + 0.48mm NCF + 0.14mm 50/125 GRIN", the relationships between the theoretical Coupling Efficiency and transmission distance are compared with experimental data. The obtained results show that an increase in the working distance of a probe causes increase of the transmission distance to maintain a higher Coupling Efficiency, and leads to gain of the waist diameter. Therefore, the comprehensive effects of the working distance, waist diameter and Coupling Efficiency must be taken into consideration in the process of optimizing the design parameters of ultra-small GRIN fiber probes.
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Coupling Efficiency of ultra-small gradient-index fiber probe
Optics Communications, 2017Co-Authors: Chi Wang, Jianmei Sun, Sun Fan, Jun Zhu, Zhiwen Yuan, Anand AsundiAbstract:Abstract In this paper, the Coupling Efficiency of ultra-small GRIN fiber probe is studied for its focusing performance. Based on the light transmission characteristics of a Gaussian beam and the principle of optical imaging, with the analytical methods, the theoretical formula is deduced for the Coupling Efficiency of ultra-small GRIN fiber probe. Experiments were set-up and conducted for verification. Per the experimental results, for an ultra-small GRIN fiber probe with the focal length of 0.4 mm, the Coupling Efficiency measured at the focusing position was 57%, and above 44% within the 0–0.6 mm range. However, for a single-mode fiber, the Coupling Efficiency dropped to 17% when the distance increased to 0.2 mm. Thus, the ultra-small GRIN fiber probe boasts a superior focusing performance and Coupling Efficiency. This paper provides a theoretical basis for the application and research on ultra-small GRIN fiber probe.
Ray T. Chen - One of the best experts on this subject based on the ideXlab platform.
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Bottom to in-plane grating coupler with high Coupling Efficiency and directionality
Terahertz RF Millimeter and Submillimeter-Wave Technology and Applications XII, 2019Co-Authors: Yixin Chen, Elham Heidari, Bonnie J. Dunbar, Volker J. Sorger, Zi Jing Wong, Ray T. Chen, Hamed DalirAbstract:Here, we have presented the first design of a bottom to in-plane grating coupler with a high Coupling Efficiency and directionality. The grating coupler consists of a high contrast grating (HCG) and an etched silicon-on-insulator (SOI) grating device. The final Coupling Efficiency is 82.2% at 1.55µm, with a 57nm 3dB bandwidth, and the directionality is 14:1 (left to right ratio). This grating coupler can be further optimized with different low index materials. This grating coupler could work as the vertical to in-plane coupler for the label free silicon photonic bio-sensor.
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on the role of evanescent modes and group index tapering in slow light photonic crystal waveguide Coupling Efficiency
Applied Physics Letters, 2011Co-Authors: Amir Hosseini, David Kwong, Harish Subbaraman, Wei Jiang, Ray T. ChenAbstract:We investigate effects of different mechanisms on Coupling Efficiency between strip waveguides and the slow light mode in photonic crystal waveguides (PCWs). Both numerical simulations and experimental results show that group index (ng) tapering improves strip-PCW butt-Coupling Efficiency when compared to a direct Coupling between a strip waveguide and a high-ng PCW. However, Coupling Efficiency is even higher when an intermediate low-ng PCW is used to couple from a strip waveguide to a high-ng PCW without an ng tapering. Our results suggest that the role of evanescent mode is more dominant in efficient Coupling between two PCWs with large ng mismatch.
Chi Wang - One of the best experts on this subject based on the ideXlab platform.
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Further study of Coupling Efficiency of ultra-small gradient-index fiber probe
Optik, 2019Co-Authors: Chi Wang, Jianmei Sun, Bin Kuang, Zhuli Wen, Anand AsundiAbstract:Abstract In this paper, the relationship between the Coupling Efficiency and transmission distance of different fiber optic probes is compared for further studying the focusing performance of ultra-small GRIN fiber probes. Taking an example of five typical ultra-small GRIN fiber probes such as single mode fiber (SMF), "SMF + 0.31mm 50/125 GRIN", "SMF + 0.36mm NCF + 0.12mm 50/125 GRIN", "SMF + 0.48mm 100/140 GRIN", "SMF + 0.48mm NCF + 0.14mm 50/125 GRIN", the relationships between the theoretical Coupling Efficiency and transmission distance are compared with experimental data. The obtained results show that an increase in the working distance of a probe causes increase of the transmission distance to maintain a higher Coupling Efficiency, and leads to gain of the waist diameter. Therefore, the comprehensive effects of the working distance, waist diameter and Coupling Efficiency must be taken into consideration in the process of optimizing the design parameters of ultra-small GRIN fiber probes.
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Coupling Efficiency of ultra-small gradient-index fiber probe
Optics Communications, 2017Co-Authors: Chi Wang, Jianmei Sun, Sun Fan, Jun Zhu, Zhiwen Yuan, Anand AsundiAbstract:Abstract In this paper, the Coupling Efficiency of ultra-small GRIN fiber probe is studied for its focusing performance. Based on the light transmission characteristics of a Gaussian beam and the principle of optical imaging, with the analytical methods, the theoretical formula is deduced for the Coupling Efficiency of ultra-small GRIN fiber probe. Experiments were set-up and conducted for verification. Per the experimental results, for an ultra-small GRIN fiber probe with the focal length of 0.4 mm, the Coupling Efficiency measured at the focusing position was 57%, and above 44% within the 0–0.6 mm range. However, for a single-mode fiber, the Coupling Efficiency dropped to 17% when the distance increased to 0.2 mm. Thus, the ultra-small GRIN fiber probe boasts a superior focusing performance and Coupling Efficiency. This paper provides a theoretical basis for the application and research on ultra-small GRIN fiber probe.
K J Ebeling - One of the best experts on this subject based on the ideXlab platform.
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butt Coupling Efficiency of vcsels into multimode fibers
IEEE Photonics Technology Letters, 1997Co-Authors: J Heinrich, E Zeeb, K J EbelingAbstract:We report a detailed study on butt Coupling efficiencies of vertical-cavity surface-emitting lasers (VCSELs) to standard graded index multimode silica fibers. Coupling Efficiency strongly depends on active laser diameter as well as index guiding and transverse mode spectrum of the laser. For typical active laser diameters of 16-20-/spl mu/m Coupling efficiencies of about 90% are obtained with weakly index guided proton-implanted vertical-cavity lasers (VCLs) whereas stronger index guided oxidized lasers show considerably lower Coupling efficiencies between 75% and 55%, depending on driving currents.
Jianmei Sun - One of the best experts on this subject based on the ideXlab platform.
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Further study of Coupling Efficiency of ultra-small gradient-index fiber probe
Optik, 2019Co-Authors: Chi Wang, Jianmei Sun, Bin Kuang, Zhuli Wen, Anand AsundiAbstract:Abstract In this paper, the relationship between the Coupling Efficiency and transmission distance of different fiber optic probes is compared for further studying the focusing performance of ultra-small GRIN fiber probes. Taking an example of five typical ultra-small GRIN fiber probes such as single mode fiber (SMF), "SMF + 0.31mm 50/125 GRIN", "SMF + 0.36mm NCF + 0.12mm 50/125 GRIN", "SMF + 0.48mm 100/140 GRIN", "SMF + 0.48mm NCF + 0.14mm 50/125 GRIN", the relationships between the theoretical Coupling Efficiency and transmission distance are compared with experimental data. The obtained results show that an increase in the working distance of a probe causes increase of the transmission distance to maintain a higher Coupling Efficiency, and leads to gain of the waist diameter. Therefore, the comprehensive effects of the working distance, waist diameter and Coupling Efficiency must be taken into consideration in the process of optimizing the design parameters of ultra-small GRIN fiber probes.
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Coupling Efficiency of ultra-small gradient-index fiber probe
Optics Communications, 2017Co-Authors: Chi Wang, Jianmei Sun, Sun Fan, Jun Zhu, Zhiwen Yuan, Anand AsundiAbstract:Abstract In this paper, the Coupling Efficiency of ultra-small GRIN fiber probe is studied for its focusing performance. Based on the light transmission characteristics of a Gaussian beam and the principle of optical imaging, with the analytical methods, the theoretical formula is deduced for the Coupling Efficiency of ultra-small GRIN fiber probe. Experiments were set-up and conducted for verification. Per the experimental results, for an ultra-small GRIN fiber probe with the focal length of 0.4 mm, the Coupling Efficiency measured at the focusing position was 57%, and above 44% within the 0–0.6 mm range. However, for a single-mode fiber, the Coupling Efficiency dropped to 17% when the distance increased to 0.2 mm. Thus, the ultra-small GRIN fiber probe boasts a superior focusing performance and Coupling Efficiency. This paper provides a theoretical basis for the application and research on ultra-small GRIN fiber probe.
