In this work, a novel one-time-programmable memory unit based on a Schottky-type p-GaN diode is proposed. During the programming process, the junction switches from a high-resistance state to a low-resistance state through Schottky junction breakdown, and the state is permanently preserved. The memory unit features a current ratio of more than 10³, a read voltage window of 6 V, a programming time of less than 10^?4 s, a stability of more than 10⁸ read cycles, and a lifetime of far more than 10 years. Besides, the fabrication of the device is fully compatible with commercial Si-based GaN process platforms, which is of great significance for the realization of low-cost read-only memory in all-GaN integration.

光子带隙光纤有着独特的结构形式、传输介质和导光机制，这使其具有传统光纤无法比拟的优点，是未来光纤陀螺的理想选择。但光子带隙光纤粗糙的纤芯内壁导致其产生强烈的背向散射次波，会使光子带隙光纤陀螺产生额外的非互易误差。为了定量分析光子带隙光纤背向散射次波强度大小，论文基于电偶极子辐射理论建立了一种简单的光子带隙光纤背向散射次波理论模型。通过聚焦离子束微纳加工法和原子力显微镜测量得到了准确的纤芯内壁表面形貌功率谱密度，进而计算得到HC-1550-02型光子带隙光纤背向散射系数理论值为2.61×10^-9/mm。通过光频域背向反射散射仪得到HC-1550-02型光子带隙光纤背向散射系数测量值为~1.82×10^-9/mm，初步验证了背向散射次波模型的正确性，为背向散射次波抑制技术研究奠定了基础。

Valley topological photonic crystals (TPCs), which are robust against local disorders and structural defects, have attracted great research interest, from theoretical verification to technical applications. However, previous works mostly focused on the robustness of topologically protected edge states and little attention was paid to the importance of the photonic bandgaps (PBGs), which hinders the implementation of various multifrequency functional topological photonic devices. Here, by systematically studying the relationship between the degree of symmetry breaking and the working bandwidth of the edge states, we present spoof surface plasmon polariton valley TPCs with broadband edge states and engineered PBGs, where the operation frequency is easy to adjust. Furthermore, by connecting valley TPCs operating at different frequencies, a broadband multifunctional frequency-dependent topological photonic device with selectively directional light transmission is fabricated and experimentally demonstrated, achieving the functions of wavelength division multiplexing and add–drop multiplexing. We provide an effective and insightful method for building multi-frequency topological photonic devices.

基于宽禁带光导半导体的固态光导微波源是高功率微波产生的一种新途径，该方案具有功率密度高、频带范围宽等特点，且其低时间抖动特性使其在功率合成方面具有巨大潜力，利用光波束形成网络构建光导微波有源相控阵是光导微波器件迈向实用的重要途径。分析了光导微波相控阵系统原理，设计了光导微波真延时网络架构，并构建了差分真延时相控阵和考虑相位随机误差的真延时相控阵的理论模型，对影响功率合成和波束扫描的关键因素开展定量分析和仿真验证。结果表明，对于发射1 GHz信号的n×10阵列，延时均方差在10 ps以下时，指向偏差小于0.13°，峰值增益损耗小于2%；延时步进精度在10 ps以下时，指向偏差小于0.2°，峰值增益损耗小于0.03%。由此提出延时精度指标，为未来更高功率、更大规模的光导微波合成技术发展提供参考。

Radio frequency/microwave-directed energy sources using wide bandgap SiC photoconductive semiconductors have attracted much attention due to their unique advantages of high-power output and multi-parameter adjustable ability. Over the past several years, benefitting from the sustainable innovations in laser technology and the significant progress in materials technology, megawatt-class output power electrical pulses with a flexible frequency in the P and L microwave wavebands have been achieved by photoconductive semiconductor devices. Here, we mainly summarize and review the recent progress of the high-power photonic microwave generation based on the SiC photoconductive semiconductor devices in the linear modulation mode, including the mechanism, system architecture, critical technology, and experimental demonstration of the proposed high-power photonic microwave sources. The outlooks and challenges for the future of multi-channel power synthesis development of higher power photonic microwave using wide bandgap photoconductors are also discussed.

深入研究了宽谱入射光的吸收、光生载流子产生，以及光生载流子的输运和复合的物理过程，提出在pin半导体结中设置若干不同能量带隙的半导体层。通过这些不同能量带隙半导体层调节不同波长入射光的吸收区域，并利用偏置电压控制不同区域光生载流子的传输和复合，进而改变探测器的光谱响应特性。根据研究结果，如果设置4层带隙梯度分布的本征层，不同偏置电压下探测器光谱响应曲线的Pearson相关系数从0.99下降到0.68，为后续的探测器光谱重构提供了有效的宽谱探测数据。