针对典型卫星轨道辐射环境下激光二极管（LD）的可靠性评估问题，对自研的975 nm GaAs基量子阱（QW）LD开展了10 MeV质子、3×10⁸~3×10¹¹ cm^-2注量的地面模拟辐照实验。结合蒙特卡罗软件仿真模拟和数学分析方法，全面研究了器件位移损伤退化规律，以及不同注量、不同辐照缺陷对器件功率特性、电压特性和波长特性等关键参数的影响。结果显示，质子辐照会引入非辐射复合中心等缺陷并破坏界面结构，导致载流子浓度降低、光电限制能力下降，宏观上体现为器件阈值电流增加、输出功率下降、波长红移和单色性受损。同时，3×10¹⁰ cm^-2以上注量的10 MeV质子等效位移损伤剂量辐照会对975 nm QW LD性能产生较大影响。

为了发挥单管半导体激光器的优势, 获得光纤耦合模块多波长、高功率、高亮度的光束输出, 利用ZEMAX软件仿真模拟, 设计了一种单管光纤耦合模块。此模块将32支输出波长分别为915 nm、975 nm, 输出功率为15 W的单管半导体激光器, 经过微透镜组快慢轴光束整形、空间合束、偏振合束、波长合束以及光束聚焦等一系列工艺后, 耦合进芯径200 μm、数值孔径0.22的光纤。模拟结果显示, 光纤输出功率467.46 W, 光纤前后耦合效率大于98.47%, 总耦合效率高于97.39%, 光功率密度高于12.86 MW/(cm2·sr), 达到了泵浦激光器和功率型器件的性能要求。使用Solidworks软件设计了相应的底板结构, 并结合ANSYS软件进行散热模拟分析, 结果显示该模块散热性能良好, 可行性较高。

The diagnosis of bacterial infections remains a major challenge in medicine. Optical imaging of bacterial infection in living animals is usually conducted with genetic reporters such as lightemitting enzymes or fluorescent proteins. However, there are many circumstances where genetic reporters are not applicable, and there is an urgent need for exogenous synthetic probes that can selectively target bacteria. Optical imaging of bacteria in vivo is much less developed than methods such as radioimaging and MRI. Furthermore near-infrared (NIR) dyes with emission wavelengths in the region of 650·900 nm can propagate through two or more centimeters of tissue and may enable deeper tissue imaging if sensitive detection techniques are employed. Here we constructed an antimicrobial peptide fragment UBI29-41-based near-infrared fluorescent imaging probe. The probe is composed of UBI29-41 conjugated to a near infrared dye ICG-Der- 02. UBI29-41 is a cationic antimicrobial peptide that targets the anionic surfaces of bacterial cells. The probe allows detection of Staphylococcus aureus infection (5×10⁷cells) in a mouse local infection model using whole animal near-infrared fluorescence imaging. Furthermore, we demonstrate that the UBI29-41-based imaging probe can selectively accumulate within bacteria. The significantly higher accumulation in bacterial infection suggests that UBI29-41-based imaging probe may be a promising imaging agent to detect bacterial infections.