Integrated traveling-wave lithium niobate modulators need relatively large device lengths to achieve low drive voltage. To increase modulation efficiency within a compact footprint, we report an integrated Fabry–Pero...Integrated traveling-wave lithium niobate modulators need relatively large device lengths to achieve low drive voltage. To increase modulation efficiency within a compact footprint, we report an integrated Fabry–Perot-type electro-optic thin film lithium niobate on insulator modulator comprising a phase modulation region sandwiched between two distributed Bragg reflectors. The device exhibits low optical loss and a high tuning efficiency of 15.7 pm/V. We also confirm the modulator's high-speed modulation performance by non-return-to-zero modulation with a data rate up to 56 Gbit/s.展开更多
This paper seeks to evaluate crack propagation properties and residual lives of metallic alloys subjected to fatigue loading at room and high temperatures. Fatigue crack growth tests were performed on Ti-6Al-4V/ELI an...This paper seeks to evaluate crack propagation properties and residual lives of metallic alloys subjected to fatigue loading at room and high temperatures. Fatigue crack growth tests were performed on Ti-6Al-4V/ELI and 7050-T7452 subjected to constant-amplitude and actual randomspectra loading at room temperature of about 25 ℃ and at high temperatures of 250 ℃ and 150 ℃ to determine their crack growth properties and residual lives. The damage mode and mechanisms at high temperature were compared with those at room temperature on the basis of the results of fractographic analysis. Temperature-dependent residual lives under actual random-spectra load history were evaluated based on a modified accumulation damage rule accounting for the load interaction.Good correlation was achieved between the predictions and actual experiments, demonstrating the practical and effective use of the proposed method.展开更多
基金partially supported by the National Key R&D Program of China(Nos.2019YFA0705000 and 2019YFB1803900)the National Natural Science Foundation of China(Nos.11690031 and 11761131001)+3 种基金the Key R&D Program of Guangdong Province(No.2018B030329001)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01X121)the Innovation Fund of WNLO(No.2018WNLOKF010)the Project of Key Laboratory of Radar Imaging and Microwave Photonics,Ministry of Education(No.RIMP2019003)。
文摘Integrated traveling-wave lithium niobate modulators need relatively large device lengths to achieve low drive voltage. To increase modulation efficiency within a compact footprint, we report an integrated Fabry–Perot-type electro-optic thin film lithium niobate on insulator modulator comprising a phase modulation region sandwiched between two distributed Bragg reflectors. The device exhibits low optical loss and a high tuning efficiency of 15.7 pm/V. We also confirm the modulator's high-speed modulation performance by non-return-to-zero modulation with a data rate up to 56 Gbit/s.
基金supported by the National Natural Science Foundation of China (No.51375033)
文摘This paper seeks to evaluate crack propagation properties and residual lives of metallic alloys subjected to fatigue loading at room and high temperatures. Fatigue crack growth tests were performed on Ti-6Al-4V/ELI and 7050-T7452 subjected to constant-amplitude and actual randomspectra loading at room temperature of about 25 ℃ and at high temperatures of 250 ℃ and 150 ℃ to determine their crack growth properties and residual lives. The damage mode and mechanisms at high temperature were compared with those at room temperature on the basis of the results of fractographic analysis. Temperature-dependent residual lives under actual random-spectra load history were evaluated based on a modified accumulation damage rule accounting for the load interaction.Good correlation was achieved between the predictions and actual experiments, demonstrating the practical and effective use of the proposed method.
