Chemical mechanical polishing （CMP） was used to polish Lithium triborate （LiB3O5 or LBO） crystal. Taguchi method was applied for optimization of the polishing parameters. Material removal rate （MRR） and surface ...Chemical mechanical polishing （CMP） was used to polish Lithium triborate （LiB3O5 or LBO） crystal. Taguchi method was applied for optimization of the polishing parameters. Material removal rate （MRR） and surface roughness are considered as criteria for the optimization. The polishing pressure, the abrasive concentration and the table velocity are important parameters which influence MRR and surface roughness in CMP of LBO crystal. Experiment results indicate that for MRR the polishing pressure is the most significant polishing parameter followed by table velocity; while for the surface roughness, the abrasive concentration is the most important one. For high MRR in CMP of LBO ctystal the optimal conditions are： pressure 620 g/cm^2, concentration 5.0 wt pct, and velocity 60 r/min, respectively. For the best surface roughness the optimal conditions are： pressure 416 g/cm^2, concentration 5.0 wt pct, and velocity 40 r/min, respectively. The contributions of individual parameters for MRR and surface roughness were obtained.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supported by the National Natural Science Foundation of China(No.50675104 and 50905086)Six High Talent Fund of Jiangsu Province(No.06-D-024)Talent Fund of NUAA(No.S0782-052)
文摘Chemical mechanical polishing （CMP） was used to polish Lithium triborate （LiB3O5 or LBO） crystal. Taguchi method was applied for optimization of the polishing parameters. Material removal rate （MRR） and surface roughness are considered as criteria for the optimization. The polishing pressure, the abrasive concentration and the table velocity are important parameters which influence MRR and surface roughness in CMP of LBO crystal. Experiment results indicate that for MRR the polishing pressure is the most significant polishing parameter followed by table velocity; while for the surface roughness, the abrasive concentration is the most important one. For high MRR in CMP of LBO ctystal the optimal conditions are： pressure 620 g/cm^2, concentration 5.0 wt pct, and velocity 60 r/min, respectively. For the best surface roughness the optimal conditions are： pressure 416 g/cm^2, concentration 5.0 wt pct, and velocity 40 r/min, respectively. The contributions of individual parameters for MRR and surface roughness were obtained.
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.
