1 064 nm, 532 nm frequency-doubled antireflection （AR） coatings with buffer layer of SiO2 between the coating and the substrate were fabricated by the electron beam evaporation technology on the substrate of lithium...1 064 nm, 532 nm frequency-doubled antireflection （AR） coatings with buffer layer of SiO2 between the coating and the substrate were fabricated by the electron beam evaporation technology on the substrate of lithium triborate （LiB3O5 or LBO） crystals. The residual reflectance of the sample is 0.07% and 0.11% at 1 064 nm and 532 nm, respectively. The adhesion and the laser-induced damage threshold （LIDT） of the sample are greater than 200 mN and 18.6 J/cm2. The strengthening mechanism of adhesion and LIDT of the buffer layer of SiO2 were discussed by considering full plastic indentation and shear theory, and spallation of a plated film induced by thermal shock stress, respectively.展开更多
Frequency-doubled antireflection coatings simultaneously effective at 1064 nm and 532 nm were deposited on the lithium triborate （LiB3O5 or LBO） crystals using the electron beam evaporation method. Comparing with th...Frequency-doubled antireflection coatings simultaneously effective at 1064 nm and 532 nm were deposited on the lithium triborate （LiB3O5 or LBO） crystals using the electron beam evaporation method. Comparing with the sample without buffer layer, it is found that the adhesion of the sample with buffer layer of SiO2 between coating and LBO substrate is improved significantly from 137.4 mN to greater than 200 mN. And the laser-induced damage threshold is increased by 20% from 15.1 J/cm^2 to 18.6 J/cm^2. The strengthening mechanism of adhesion of the buffer layer of SiO2 is discussed by considering full plastic indentation and shear theory.展开更多
A wideband tunable frequency-doubling optoelectronic oscillator （FD-OEO） is proposed and experimentally demonstrated based on a polarization modulator and an optical bandpass filter （OBPF）. The central frequency o...A wideband tunable frequency-doubling optoelectronic oscillator （FD-OEO） is proposed and experimentally demonstrated based on a polarization modulator and an optical bandpass filter （OBPF）. The central frequency of the correspondingly fundamental OEO could be adjusted by tuning the bandwidth and central frequency of the OBPF, which could also be regarded as a photonic-assisted tunable microwave filter. The frequency tuning range of the FD-OEO covers from 9.5 to 32.8？GHz, and the single sideband phase noise of the fundamental signal is lower than -100dBc/Hz at an offset of 10？kHz. Moreover, the frequency stability of the generated signal is investigated by measuring its Allan deviation. The Allan deviation of the generated fundamental signal at 10？GHz is 2.39×10^-9.展开更多
A 60-mW solid-state deep ultraviolet(DUV)laser at 193 nm with narrow linewidth is obtained with two stages of sum frequency generation in LBO crystals.The pump lasers,at 258 and 1553 nm,are derived from a homemade Yb-...A 60-mW solid-state deep ultraviolet(DUV)laser at 193 nm with narrow linewidth is obtained with two stages of sum frequency generation in LBO crystals.The pump lasers,at 258 and 1553 nm,are derived from a homemade Yb-hybrid laser employing fourth-harmonic generation and Er-doped fiber laser,respectively.The Yb-hybrid laser,finally,is power scaling by a 2 mm×2 mm×30 mm Yb:YAG bulk crystal.Accompanied by the generated 220-mW DUV laser at 221 nm,the 193-nm laser delivers an average power of 60 mW with a pulse duration of 4.6 ns,a repetition rate of 6 kHz,and a linewidth of∼640 MHz.To the best of our knowledge,this is the highest power of 193-and 221-nm laser generated by an LBO crystal ever reported as well as the narrowest linewidth of 193-nm laser by it.Remarkably,the conversion efficiency reaches 27%for 221 to 193 nm and 3%for 258 to 193 nm,which are the highest efficiency values reported to date.We demonstrate the huge potential of LBO crystals for producing hundreds of milliwatt or even watt level 193-nm laser,which also paves a brand-new way to generate other DUV laser wavelengths.展开更多
基金Funded by the Doctorial Start-up Fund of the Department of Science and Technology of Liaoning Province (20081030)
文摘1 064 nm, 532 nm frequency-doubled antireflection （AR） coatings with buffer layer of SiO2 between the coating and the substrate were fabricated by the electron beam evaporation technology on the substrate of lithium triborate （LiB3O5 or LBO） crystals. The residual reflectance of the sample is 0.07% and 0.11% at 1 064 nm and 532 nm, respectively. The adhesion and the laser-induced damage threshold （LIDT） of the sample are greater than 200 mN and 18.6 J/cm2. The strengthening mechanism of adhesion and LIDT of the buffer layer of SiO2 were discussed by considering full plastic indentation and shear theory, and spallation of a plated film induced by thermal shock stress, respectively.
基金Fundeded by the Doctorial Start-up Fund of the Department of Science and Technology of Liaoning Province(20081030)S&T Plan Project of the Educational Department of Liaoning Province(2008224)
文摘Frequency-doubled antireflection coatings simultaneously effective at 1064 nm and 532 nm were deposited on the lithium triborate （LiB3O5 or LBO） crystals using the electron beam evaporation method. Comparing with the sample without buffer layer, it is found that the adhesion of the sample with buffer layer of SiO2 between coating and LBO substrate is improved significantly from 137.4 mN to greater than 200 mN. And the laser-induced damage threshold is increased by 20% from 15.1 J/cm^2 to 18.6 J/cm^2. The strengthening mechanism of adhesion of the buffer layer of SiO2 is discussed by considering full plastic indentation and shear theory.
基金Supported by the National Natural Science Foundation of China under Grant No 61675196the National Basic Research Program of China under Grant No 2014CB340102+1 种基金the National High-Tech Research and Development Program of China under Grant No 2015AA016903the Open Research of Beijing University of Posts and Telecommunications under Grant No IOOC2013A002
文摘A wideband tunable frequency-doubling optoelectronic oscillator （FD-OEO） is proposed and experimentally demonstrated based on a polarization modulator and an optical bandpass filter （OBPF）. The central frequency of the correspondingly fundamental OEO could be adjusted by tuning the bandwidth and central frequency of the OBPF, which could also be regarded as a photonic-assisted tunable microwave filter. The frequency tuning range of the FD-OEO covers from 9.5 to 32.8？GHz, and the single sideband phase noise of the fundamental signal is lower than -100dBc/Hz at an offset of 10？kHz. Moreover, the frequency stability of the generated signal is investigated by measuring its Allan deviation. The Allan deviation of the generated fundamental signal at 10？GHz is 2.39×10^-9.
基金supported by the Research Project of Aerospace Information Research Institute,Chinese Academy of Sciences (Grant Nos.E1Z1D101 and E2Z2D101)the Project of Chinese Academy of Sciences (Grant No.E33310030D)the Guangzhou Basic and Applied Basic Research Foundation (Grant Nos.2023A04J0336 and 2023A04J0021).
文摘A 60-mW solid-state deep ultraviolet(DUV)laser at 193 nm with narrow linewidth is obtained with two stages of sum frequency generation in LBO crystals.The pump lasers,at 258 and 1553 nm,are derived from a homemade Yb-hybrid laser employing fourth-harmonic generation and Er-doped fiber laser,respectively.The Yb-hybrid laser,finally,is power scaling by a 2 mm×2 mm×30 mm Yb:YAG bulk crystal.Accompanied by the generated 220-mW DUV laser at 221 nm,the 193-nm laser delivers an average power of 60 mW with a pulse duration of 4.6 ns,a repetition rate of 6 kHz,and a linewidth of∼640 MHz.To the best of our knowledge,this is the highest power of 193-and 221-nm laser generated by an LBO crystal ever reported as well as the narrowest linewidth of 193-nm laser by it.Remarkably,the conversion efficiency reaches 27%for 221 to 193 nm and 3%for 258 to 193 nm,which are the highest efficiency values reported to date.We demonstrate the huge potential of LBO crystals for producing hundreds of milliwatt or even watt level 193-nm laser,which also paves a brand-new way to generate other DUV laser wavelengths.
