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81.
高掺锌富锂铌酸锂体抗光损伤能力的研究 总被引:1,自引:0,他引:1
以Czochralski法生长Zn(6mol%):LiNbO3,Li/Nb=0.94,0.97,1,1.02。测试晶体的光损伤阈值。采用质子交换法制作高掺锌富锂铌酸锂晶体光波导,研究了它们的抗光损伤能力。 相似文献
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This paper presents the characterization of single-mode waveguides for 980 and 1550 nm wavelengths. High quality planar waveguide structure was fabricated from Y1 − xErxAl3(BO3)4 multilayer thin films with x = 0.02, 0.05, 0.1, 0.3, and 0.5, prepared through the polymeric precursor and sol-gel methods using spin-coating. The propagation losses of the planar waveguides varying from 0.63 to 0.88 dB/cm were measured at 632.8 and 1550 nm. The photoluminescence spectra and radiative lifetimes of the Er3+ 4I13/2 energy level were measured in waveguiding geometry. For most samples the photoluminescence decay was single exponential with lifetimes in between 640 μs and 200 μs, depending on the erbium concentration and synthesis method. These results indicate that Er doped YAl3(BO3)4 compounds are promising for low loss waveguides. 相似文献
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Deepening Insights of Charge Transfer and Photophysics in a Novel Donor–Acceptor Cocrystal for Waveguide Couplers and Photonic Logic Computation
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Shui‐Jing Tang Shuai Liu Xiao‐Chong Yu Qinghai Song Qihuang Gong Yun‐Feng Xiao 《Advanced materials (Deerfield Beach, Fla.)》2018,30(25)
Ultrasensitive and rapid detection of nano‐objects is crucial in both fundamental studies and practical applications. Optical sensors using evanescent fields in microcavities, plasmonic resonators, and nanofibers allow label‐free detection down to single molecules, but practical applications are severely hindered by long response time and device reproducibility. Here, an on‐chip dense waveguide sensor to monitor single unlabeled nanoparticles in a strong optical evanescent field is demonstrated. The spiral nanowaveguide design enables two orders of magnitude enhancement in sensing area compared to a straight waveguide, significantly improving the particle capture ability and shortening the target analysis time. In addition, the measurement noise is suppressed to a level of 10?4 in the transmitted power, pushing the detection limit of single particles down to the size of 100 nm. The waveguide sensor on the silicon‐on‐isolator platform can be fabricated reproducibly by the conventional semiconductor processing and compatible with surface functionalization chemistries and microfluidics, which could lead to widespread use for sensing in environmental monitoring and human health. 相似文献
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An optical waveguide structure consisting of side-polished single-mode fiber covered with thin a-Si:H planar waveguide is studied as a channel-dropping narrow-band filter and fiber-optic polarizer. Spectral and polarization characteristics of the structure are measured in the wavelength region of 600–1600 nm, for the different values of the a-Si:H film thickness and the superstrate refractive index. The FWHM of the filter is about 8 nm for the asymmetric waveguide and 10 nm for the symmetric one. The discrimination of the resonance minima for two polarizations varies from several tens for the symmetric PWG up to several hundreds of nanometers for the asymmetric PWG. The optical losses in the off-resonance region are less than 0.3 dB. The measured value of the extinction coefficient of the fiber-optical polarizer is 32.5 dB. 相似文献