硅酸盐学报2025，Vol.53Issue(12)：3461-3467,7.DOI:10.14062/j.issn.0454-5648.20240716
激光二极管泵浦黄光掺镝硼酸钆镁激光器
Laser Diode-Pumped Yellow Dy3+:GdMgB5O10 Laser
摘要
Abstract
Introduction Visible-light lasers have applications in biology,medicine,and detection.Compared to conventional nonlinear frequency doubling methods for obtaining visible light lasers,it is possible to prepare laser crystals that directly emit a visible light via doping with rare-earth elements such as Pr3+,Sm3+,Tb3+,and Dy3+.For yellow light lasers,doping with Dy3+is more suitable.The existing Dy3+-doped laser crystals are still at the theoretical stage,with a few experimental cases.Recently,a high-quality Dy3+-doped borate crystal GdMgB5O10(Dy3+:GMB)is prepared to produce a yellow light laser at a wavelength of 580 nm.In this study,a plane-plane cavity laser was assembled using a 3 mm×3 mm×20 mm Y-cut Dy3+:GMB crystal with a 444 nm blue LD pump,achieving a laser output at 579.3 nm.The maximum output power reached 161 mW with a slope efficiency of 3.7%as using different output couplers at different transmission rates. Methods In this experiment,a 444 nm blue LD with a maximum power of 12 W was used as a pump source.The model of the blue LD pump was LSR444CP4-12W.The pump output a spatial light directly without fiber coupling and used air cooling to maintain a temperature of 25℃.The beam size at the output of the pump was 4.3 mm horizontally and 4.1 mm vertically.The beam remained parallel within 0.5 m and could be approximated as a parallel light.A plano-convex lens with a focal length of 150 mm was used.A Y-cut Dy:GMB crystal with the dimensions of 3 mm×3 mm×20 mm was used.The doping concentration of Dy3+ in the crystal was 6.08%,and the end faces of the crystal were polished but not coated for the blue wavelength band.The Dy:GMB crystal was wrapped in indium foil and placed in a water-cooled copper block,with the copper block's water cooling set to 20℃.The polarization direction of the pump light was vertical.Based on the polarization bsorption efficiency of the Dy:GMB crystal along different axes,the crystal was positioned in an optical path.The pump light absorption efficiency of the crystal was measured under non-lasing conditions.When the crystal was placed,the pump light absorption efficiency was 55%.The laser resonator consisted of two coated plane mirrors.IM was the input mirror for the pump light,with coating arameters that could reduce reflection and increase transmission at 444 nm.The measured transmission at 444 nm was 96%.It also had a high reflectivity at 579 nm with a reflectivity of≥99.8%.OC was the output coupler mirror,and the coated mirrors with 579 nm transmission rates of 1%and 2%were used.A long-pass edge filter with a cutoff wavelength of 450 nm was placed at the laser output to effectively reduce the impact of pump light on power measurements.After the output power measurement,a Glan prism was used to analyze the polarization of the output laser. Results and discussion The output wavelength of the experimental laser is 579.3 nm,without other wavelengths detected.In the experiment with an OC transmission rate of 1%,a laser generation begins when the crystal absorbes 1.94 W of pump power,achieving a maximum output power of 161 mW and a slope efficiency of 3.7%.In the experiment with an OC transmission rate of 2%,a laser generation starts at an absorption power of 2.81 W,having a maximum output power of 129 mW with a slightly lower slope efficiency of 3.6%.No saturation in laser output power occurs in either set of experiments.The laser threshold and output power using an OC transmission rate of 1%are slightly greater than those using an OC transmission rate of 2%,which is consistent with the results reported in a previous study.Based on the slope efficiency,it is estimated that under the same pump absorption power,the maximum output power of the laser in this experiment can exceed 628 mW.There are three methods to improve the output power and slope efficiency of the laser via comparing the performance of the crystal in two separate experiments.The first method is to use a higher-power and higher-quality pump to enhance the absorption efficiency of the Dy:GMB crystal.The second method is to employ different types of laser cavities and optimize the coating parameters of the IM and OC,as well as shape the pump beam to achieve better spatial mode matching between the pump light and the laser cavity.The third method is to optimize the growth process to obtain X-cut or Z-cut crystals of sufficient length with varying Dy doping concentrations,as the emission cross-section of the Dy:GMB crystal is maximum at 578.5 nm along the E//Y direction. Conclusions A 579.3 nm yellow laser output with a maximum power of 161 mW and a slope efficiency of 3.7%was obtained using a plane-plane cavity laser setup with Dy:GMB crystal pumped by a 444 nm blue LD.An application potential of the crystal could be achieved via comparing the initial laser experiments with the same crystal using blue LDs at different wavelengths.This study could provide insights for future improvements in the output power and slope efficiency of lasers constructed with Dy:GMB crystals.关键词
蓝光激光二极管泵浦/平平腔/黄光激光Key words
blue Laser diode pump/plane-plane cavity/yellow laser分类
信息技术与安全科学引用本文复制引用
PAN Shengyuan,JIANG Zeqian,HUANG Yisheng,LI Bingxuan,LIN Zhoubin,ZHANG Ge..激光二极管泵浦黄光掺镝硼酸钆镁激光器[J].硅酸盐学报,2025,53(12):3461-3467,7.基金项目
国家重点研发计划(2022YFB3605703) （2022YFB3605703）
国家自然科学基金(U21A20508,62105334) （U21A20508,62105334）
中国科学院青年创新促进会项目(2022303) （2022303）
中国科学院技术支撑人才专项(2022000061) （2022000061）
中国科学院科研仪器设备研制项目(YZLY202001) （YZLY202001）
中国科学院海西研究院自主部署项目(CXZX-2023-JQ01,CXZX-2022-GH09),中国福建光电信息科学与技术创新实验室项目(2024CXY108,2020ZZ108,2021ZZ118). （CXZX-2023-JQ01,CXZX-2022-GH09）
