表面菱形孔795 nm VCSEL的偏振特性  

Polarization Characteristics of 795 nm VCSELs with Surface Rhombus Holes

作　　者：付秋雪 孙玉润 于淑珍[2] 范屹梁[1,2] 仇伯仓 董建荣 Fu Qiuxue;Sun Yurun;Yu Shuzhen;Fan Yiliang;Qiu Bocang;Dong Jianrong(School of Nano-Tech and Nano-Bionics,University of Science and Technology of China,Hefei 230026,China;Key Laboratory of Nano Devices and Applications,Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences,Suzhou 215123,China;School of Electronics and Communication Engineering,Quanzhou University of Information Engineering,Quanzhou 362000,China)

机构地区：[1]中国科学技术大学纳米技术与纳米仿生学院,合肥230026 [2]中国科学院苏州纳米技术与纳米仿生研究所纳米器件与应用重点实验室,江苏苏州215123 [3]泉州信息工程学院电子与通信工程学院,福建泉州362000

出　　处：《半导体技术》2024年第7期609-617,共9页Semiconductor Technology

摘　　要：795 nm垂直腔面发射激光器(VCSEL)作为铷基芯片级原子钟(Rb-CSAC)的光源,其输出光的偏振不稳定会降低Rb-CSAC的稳定度和精确度。为了满足Rb-CSAC对795 nm VCSEL偏振稳定的需求,设计了一种具有表面菱形孔的偏振稳定的795 nm VCSEL。通过有限时域差分(FDTD)法计算了VCSEL的偏振特性,结果表明VCSEL的顶部分布式布拉格反射镜(DBR)在表面菱形孔的长轴和短轴方向具有不同的反射率。反射率高的偏振模式阈值增益低,成为VCSEL优先激射的主导偏振模式。为进一步提高VCSEL的偏振抑制比(OPSR),将VCSEL的氧化孔制作成尺寸为5.5μm×4.1μm的菱形。对不同长、短轴的表面菱形孔795 nm VCSEL进行偏振测试,结果表明,当表面菱形孔的尺寸为4μm×6μm,且菱形氧化孔的长轴与表面菱形孔的长轴相互垂直时,VCSEL的OPSR可达到16.22 dB。795 nm vertical cavity surface emitting lasers(VCSELs)are the light source of the rubidium-based chip scale atomic clock(Rb-CSAC),of which the polarization instability may reduce the stability and accuracy of the Rb-CSAC.The polarization-stabilized 795 nm VCSEL with surface rhombus holes was designed to meet the requirement of polarization stability for 795 nm VCSELs used in Rb-CSAC.The polarization characteristics of VCSELs were calculated by the finite dfference time domain(FDTD)method.The results show that the reflectivity difference along the major and minor axes of the surface rhombus holes is induced when integrating the surface rhombus holes into the top distributed Bragg reflectors(DBRs)of VCSELs.The polarization mode with high reflectivity becomes the priority lasing dominant mode of VCSELs due to the low threshold gain.A rhombus oxide aperture of 5.5μmX 4.1μm was employed in VCSELs to further improve the polarization suppression ratio(OPSR).Polarization test results of 795 nm VCSELs with surface rhombus holes of varying major and minor axes indicate that the OPSR reaches 16.22 dB for VCSELs with a rhombus surface hole of 4μmx6μm when the major axis of the surface rhombus holes is perpendicular to that of the rhombus oxide aperture.

关 键 词：垂直腔面发射激光器(VCSEL) 表面菱形孔 偏振控制 芯片级原子钟(CSAC) 分布式布拉格反射镜(DBR) 

分 类 号：TN248.4[电子电信—物理电子学]