An approach for frequency division of an optical pulse train (OPT) based on an optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. When the OPT is injected into the OEO, a microwave signal with a frequency equaling fractional multiples of the repetition rate of the OPT is generated. This signal is then fed back to the OEO, maintaining its oscillation, while simultaneously serving as the control signal of a Mach–Zehnder modulator (MZM) in the OEO. The MZM acts as an optical switch, permitting specific pulses to pass through while blocking others. As a result, the repetition rate of the OPT is manipulated. A proof-of-concept experiment is carried out. Frequency division factors of 2 and 3 are successfully achieved. The phase noises of the OPT before and after the frequency division are investigated. Compared to previously reported systems, no external microwave source and sophisticated synchronization structure are needed.

随着电磁环境的日益复杂，电子设备面临的电磁威胁愈加严峻。光电系统作为高灵敏集成化电子设备，强电磁脉冲能量耦合进入系统内部，影响防护能力本就薄弱的光电系统的正常运行。为明晰典型光电系统强电磁耦合过程，通过仿真分析不同强电磁辐照条件下筒型、侧窗型和多窗口型三种典型光电系统的强电磁耦合情况，提取了光电系统强电磁耦合特征及其制约因素，验证了光电系统进行强电磁防护加固的必要性和紧迫性。为解决光电系统强电磁防护能力薄弱的问题，通过仿真分析，验证了透明电磁防护窗口的强电磁加固效能；开展了基于支撑台阶与导电侧壁的电磁缝隙防护加固方法研究，分析了透明防护窗口缝隙耦合泄露的关键安装结构参数，提出了一种非电接触式装配缝隙强电磁防护加固方法。经测试，当缝隙防护结构长度为6 mm时，在0.2～4 GHz频率范围光电系统平均强电磁防护效能提升4.51 dB。研究结果为光电系统强电磁防护能力提升提供了理论指导和具体解决方案。

随着信息化时代的高速发展，对微电子器件中光电材料的选择、新功能的开发提出了更高的要求。传统光电器件大多利用半导体材料在光照下电导率增加的正光电导性效应进行功能化设计。近年来，研究发现还存在另一种反常的光电导效应——负光电导（Negative photoconductivity，NPC），即在光照条件下电导率降低，由于其在光电探测、逻辑器件、神经形态器件、低功耗非易失性存储器方面的潜在应用而备受关注。NPC的产生机制一般包括载流子的俘获效应、表面分子的吸附-解吸、表面等离子体极化激元和局域表面等离子体共振、光辐射热效应等。本文详细讨论了不同光电器件中NPC产生的物理机制，分析了材料选择、器件结构设计、能带结构变化对不同异质结器件中NPC效应的影响，概括了光电器件中负光电导效应的实际应用，这为光电器件的性能优化和新型光电器件设计提供了重要参考，为未来异质结光电信息器件实现尺寸更小、光导增益更高、速率更快、功耗更低奠定了科学基础。

Two-dimensional (2D) WSe₂ has received increasing attention due to its unique optical properties and bipolar behavior. Several WSe₂-based heterojunctions exhibit bidirectional rectification characteristics, but most devices have a lower rectification ratio. In this work, the Bi₂O₂Se/WSe₂ heterojunction prepared by us has a type Ⅱ band alignment, which can vastly suppress the channel current through the interface barrier so that the Bi₂O₂Se/WSe₂ heterojunction device has a large rectification ratio of about 10⁵. Meanwhile, under different gate voltage modulation, the current on/off ratio of the device changes by nearly five orders of magnitude, and the maximum current on/off ratio is expected to be achieved 10⁶. The photocurrent measurement reveals the behavior of recombination and space charge confinement, further verifying the bidirectional rectification behavior of heterojunctions, and it also exhibits excellent performance in light response. In the future, Bi₂O₂Se/WSe₂ heterojunction field-effect transistors have great potential to reduce the volume of integrated circuits as a bidirectional controlled switching device.

Near-infrared (NIR) light has shown great potential for military and civilian applications owing to its advantages in the composition of sunlight, invisibility to human eyes, deeper penetration into biological tissues, and low optical loss in optical fibers. Therefore, organic optoelectronic materials that can absorb or emit NIR light have aroused great scientific interest in basic science and practical applications. Based on these NIR organic optoelectronic materials, NIR optoelectronic devices have been greatly improved in performance and application. In this review, the representative NIR organic optoelectronic materials used in organic solar cells, organic photodetectors, organic light-emitting diodes, organic lasers, and organic optical waveguide devices are briefly introduced, and the potential applications of each kind of device are briefly summarized. Finally, we summarize and take up the development of NIR organic optoelectronic materials and devices.

Artificial synapses utilizing spike signals are essential elements of new generation brain-inspired computers. In this paper, we realize light-stimulated adaptive artificial synapse based on nanocrystalline zinc oxide film. The artificial synapse photoconductivity shows spike-type signal response, long and short-term memory (LTM and STM), STM-to-LTM transition and paired-pulse facilitation. It is also retaining the memory of previous exposures and demonstrates spike-frequency adaptation properties. A way to implement neurons with synaptic depression, tonic excitation, and delayed accelerating types of response under the influence of repetitive light signals is discussed. The developed artificial synapse is able to become a key element of neuromorphic chips and neuromorphic sensorics systems.

With the advancement of deep learning and neural networks, the computational demands for applications in wearable devices have grown exponentially. However, wearable devices also have strict requirements for long battery life, low power consumption, and compact size. In this work, we propose a scalable optoelectronic computing system based on an integrated optical convolution acceleration core. This system enables high-precision computation at the speed of light, achieving 7-bit accuracy while maintaining extremely low power consumption. It also demonstrates peak throughput of 3.2 TOPS (tera operations per second) in parallel processing. We have successfully demonstrated image convolution and the typical application of an interactive first-person perspective gesture recognition application based on depth information. The system achieves a comparable recognition accuracy to traditional electronic computation in all blind tests.

类脑神经形态计算通过电子或光子器件集成来模拟人脑结构和功能。人工突触是类脑系统中数量最多的计算单元。忆阻器可模拟突触功能, 并具有优异的尺寸缩放性和低能耗, 是实现人工突触的理想元器件。利用欧姆定律和基尔霍夫定律, 忆阻器交叉阵列可执行并行的原位乘累加运算, 从而大幅提升类脑系统处理模拟信号的速度。氧化物制备容易, 和CMOS工艺兼容性强, 是使用最广泛的忆阻器材料。本文梳理了氧化物忆阻器的研究进展, 分别讨论了电控、光电混合调控和全光控忆阻器, 主要聚焦阻变机理、器件结构和性能。电控忆阻器工作一般会产生微结构变化和焦耳热, 将严重影响器件稳定性, 改进器件结构和材料成分可有效改善器件性能。利用光信号调控忆阻器电导, 不仅能降低能耗, 而且可避免产生微结构变化和焦耳热, 从而有望解决稳定性难题。此外, 光控忆阻器能直接感受光刺激, 单器件即可实现感/存/算功能, 可用于研发新型视觉传感器。因此, 全光控忆阻器的实现为忆阻器的研究和应用打开了一扇新窗口。