采用金属有机化学气相沉积（MOCVD）工艺在p-GaAs（100）衬底上外延了Ga₂O₃薄膜并制备了n-Ga₂O₃/p-GaAs异质结日盲紫外探测器。通过X射线衍射仪、原子力显微镜、场发射扫描电子显微镜等方法对Ga₂O₃薄膜表面形貌、晶体质量进行了测试与分析。结果表明，Ga₂O₃薄膜呈单一晶向，薄膜表面平整且为Volmer-Weber模式外延。测试表明，n-Ga₂O₃/p-GaAs异质结探测器具有明显的整流特性。器件在5 V反向偏压和紫外光（254 nm）照射下实现了超过3.0×10⁴的光暗电流比、7.0 A/W的响应度、3412%的外量子效率、4.6×10¹³ Jones的探测率。我们利用TCAD软件对器件结构进行仿真，得到了器件内的电场分布和能带结构，并分析了器件的工作原理。该异质结探测器性能较好，制造工艺简单，为Ga₂O₃超灵敏日盲紫外探测器的研制提供了新途径。

直接调制半导体激光器因其具有高速传输、高可靠和低成本等特点，成为应用在第五代移动通信技术（5G）前传和数据中心中的高性价比光源。高速直接调制半导体激光器性能提升已有许多研究，文章分别从无制冷宽温工作高速半导体激光器研究方面和超高速半导体激光器方面对高速直接调制半导体激光器的基本理论和发展历程进行了综述，分析各自的优缺点，并介绍了研发团队在这些方面取得的部分进展。

基于非线性偏振旋转（nonlinear polarization rotation, NPR）锁模机制的光纤激光器因其结构紧凑、可靠性高而备受关注。基于这一锁模原理设计并搭建了掺镱光纤飞秒激光器。当双向泵浦功率为380 mW，在1030 nm波段获得了基频重复率为22.8 MHz的锁模脉冲。脉冲宽度为224 fs，平均功率180 mW，单脉冲能量8 nJ，10 dB带宽约为40 nm，信噪比大于50 dB。该激光器采用环形腔结构产生稳定的锁模飞秒脉冲输出，可实现自启动锁模。泵浦功率增加到1.6 W可观察到最高三阶被动谐波锁模，三次谐波对应68.5 MHz重复频率。该激光器由于在线宽、脉宽、脉冲能量上的优势，在光谱测量、拉曼成像等领域具有应用意义。

Metasurfaces, two-dimensional (2D) or quasi-2D arrays of dielectric or metallic meta-atoms, offer a compact and novel platform to manipulate the amplitude, phase, and polarization of incoming wavefronts in a desired manner by engineering the geometry of meta-atoms. In polarization control, spin-insensitive metasurfaces have attracted significant attention due to the robustness of circular polarization against the beam misalignment and multi-path effects. Till now, several efforts have been made to realize polarization-insensitive metasurfaces for circularly polarized (CP) wavefront manipulation; however, these metasurfaces only consider the cross-polarization channels and keep the co-polarization channels abandoned. Such metasurfaces cannot be considered truly spin-insensitive, as one has to carefully choose the analyzer at output. Here, by combining the polarization-insensitive geometric phase and engineered propagation phase, we propose a spin-insensitive design principle based on metasurfaces that can perform identical functionality (on co- and cross-polarization channels) irrespective of the handedness of incident/transmitted light. As a proof of concept, we design and numerically realize two types of spin-insensitive wavefront engineering devices: (1) spin-insensitive meta-hologram and (2) spin-insensitive beam deflector with power splitting functionality. The proposed work is expected to open up new avenues for developing spin-independent metasurfaces-based devices.

针对相位生成载波解调算法严重依赖于调制深度，解调准确性和稳定性不高的问题，在传统PGC-Arctan算法框架中引入微分自相除运算环节，消除两路混频信号中调制深度的影响，再将两路信号进行相除得到包含相位信息正切平方项的信号，最后通过开方和反正切运算实现振动信号的解调。对不同调制深度和不同信噪比的信号解调仿真结果表明，该算法能够消除调制深度的不利影响，相比于其他常见的算法具有更好的解调效果。搭建实验平台进一步对仿真结果进行验证，实验数据表明，在不同的调制深度下，该算法的幅值误差最小为0.105%，总谐波失真最小为0.068%。此外，算法动态范围最高可达62.5 dB。综合分析结果验证了该算法能够有效地抑制调制深度影响，体现了其良好的稳定性和抗噪性，在高性能光纤振动传感系统中具有良好的应用前景。