铌酸锂(LiNbO_(3),LN)是一种集声光、电光、弹光、光折变等优越物理特性于一身的多功能晶体,不仅被誉为“光学硅”,更有学者提出人类正在进入“铌酸锂谷”时代,其优异的光电性能使基于其的各类光电器件在人工智能、光电混合集成等新兴...铌酸锂(LiNbO_(3),LN)是一种集声光、电光、弹光、光折变等优越物理特性于一身的多功能晶体,不仅被誉为“光学硅”,更有学者提出人类正在进入“铌酸锂谷”时代,其优异的光电性能使基于其的各类光电器件在人工智能、光电混合集成等新兴领域具有广阔的应用前景。光折变效应是LN晶体非常重要的特性。随着基于LN的光电器件向微纳级尺寸迅速发展,光折变效应在微纳级尺寸也已逐渐显现。LN单晶是在非绝缘体上采用铌酸锂单晶薄膜(Lithium Niobate on Insulator,LNOI)技术制备各类器件的基材,可通过掺杂合适的杂质离子来调控光折变性能。相对于传统的低价态阳离子(化合价<铌离子+5价),近年来发现掺入高价态阳离子(化合价≥铌离子+5价)更有利于提升LN晶体的光折变性能。本文综述了已有报道的高价态阳离子掺杂LN晶体光折变性能的研究成果,归纳总结出掺钒、钼、铀、铋等高价态离子可以显著提升LN晶体的光折变性能,尤其是能够有效缩短光折变响应时间,这有利于LN在微环谐振器、可编程光子器件、非线性光子器件等微纳器件领域的应用。同时,提出未来可围绕高价态离子掺杂LN,在高质量大尺寸晶体生长技术、光折变机理、其他具有孤对电子的离子掺杂、基于高价态离子掺杂LN的光电器件这四方面进行研究。展开更多
Based on a 2-D hydrodynamic model, a vertically integrated eutrophication model was developed. The physical sub-model can be used for calculation of water density at different depths, and the water quality sub-model w...Based on a 2-D hydrodynamic model, a vertically integrated eutrophication model was developed. The physical sub-model can be used for calculation of water density at different depths, and the water quality sub-model was used for calculation of algal growth. The cohesive and non-cohesive sediments were simulated separately with different methods. The light extinction coefficient used in the underwater light regime sub-model was linearly related to the sum of sediment and phytoplankton biomass. Some components less important to the model were simplified to improve practicability and calculation efficiency. Using field data from Fuchunjiang Reservoir, we calculated the sensitivity of ecological parameters included in this model and validated the model. The results of sensitivity analysis showed that the parameters strongly influenced the phytoplankton biomass, including phytoplankton maximum growth rate, respiration rate, non-predatory mortality rate, settling rate, zooplankton maximum filtration rate, specific extinction coefficient for suspended solids and sediment oxygen demand rate. The model was calibrated by adjusting these parameters. Total chlorophyll α （chl-α） concentrations at different layers in the water column were reproduced very well by the model simulations. The simulated chl-α values were positively correlated to the measured values with Pearson correlation coefficient of 0.92. The mean difference between measured and simulated chl-α concentrations was 12% of the measured chl-α concentration. Measured and simulated DO concentrations were also positively correlated （r = 0.74） and the mean difference was 4% of measured DO concentrations. The successful validation of model indicated that it would be very useful in water quality management and algal bloom prediction in Fuchunjiang Reservoir and a good tool for water quality regulation of other fiver-style reservoirs.展开更多
文摘铌酸锂(LiNbO_(3),LN)是一种集声光、电光、弹光、光折变等优越物理特性于一身的多功能晶体,不仅被誉为“光学硅”,更有学者提出人类正在进入“铌酸锂谷”时代,其优异的光电性能使基于其的各类光电器件在人工智能、光电混合集成等新兴领域具有广阔的应用前景。光折变效应是LN晶体非常重要的特性。随着基于LN的光电器件向微纳级尺寸迅速发展,光折变效应在微纳级尺寸也已逐渐显现。LN单晶是在非绝缘体上采用铌酸锂单晶薄膜(Lithium Niobate on Insulator,LNOI)技术制备各类器件的基材,可通过掺杂合适的杂质离子来调控光折变性能。相对于传统的低价态阳离子(化合价<铌离子+5价),近年来发现掺入高价态阳离子(化合价≥铌离子+5价)更有利于提升LN晶体的光折变性能。本文综述了已有报道的高价态阳离子掺杂LN晶体光折变性能的研究成果,归纳总结出掺钒、钼、铀、铋等高价态离子可以显著提升LN晶体的光折变性能,尤其是能够有效缩短光折变响应时间,这有利于LN在微环谐振器、可编程光子器件、非线性光子器件等微纳器件领域的应用。同时,提出未来可围绕高价态离子掺杂LN,在高质量大尺寸晶体生长技术、光折变机理、其他具有孤对电子的离子掺杂、基于高价态离子掺杂LN的光电器件这四方面进行研究。
基金supported by the National Natural Sci-ence Foundation of China (No. 40730529, 40501078)the Chinese Academy of Sciences (No. KZCX2-YW-419)the Department of Science and Technology of Zhejiang Province (No. 2005C13001)
文摘Based on a 2-D hydrodynamic model, a vertically integrated eutrophication model was developed. The physical sub-model can be used for calculation of water density at different depths, and the water quality sub-model was used for calculation of algal growth. The cohesive and non-cohesive sediments were simulated separately with different methods. The light extinction coefficient used in the underwater light regime sub-model was linearly related to the sum of sediment and phytoplankton biomass. Some components less important to the model were simplified to improve practicability and calculation efficiency. Using field data from Fuchunjiang Reservoir, we calculated the sensitivity of ecological parameters included in this model and validated the model. The results of sensitivity analysis showed that the parameters strongly influenced the phytoplankton biomass, including phytoplankton maximum growth rate, respiration rate, non-predatory mortality rate, settling rate, zooplankton maximum filtration rate, specific extinction coefficient for suspended solids and sediment oxygen demand rate. The model was calibrated by adjusting these parameters. Total chlorophyll α （chl-α） concentrations at different layers in the water column were reproduced very well by the model simulations. The simulated chl-α values were positively correlated to the measured values with Pearson correlation coefficient of 0.92. The mean difference between measured and simulated chl-α concentrations was 12% of the measured chl-α concentration. Measured and simulated DO concentrations were also positively correlated （r = 0.74） and the mean difference was 4% of measured DO concentrations. The successful validation of model indicated that it would be very useful in water quality management and algal bloom prediction in Fuchunjiang Reservoir and a good tool for water quality regulation of other fiver-style reservoirs.
