Recently, the two-dimensional (2D) form of Ruddlesden-Popper perovskite (RPP) has been widely studied. However, the synthesis of one-dimensional (1D) RPP is rarely reported. Here, we fabricated a photodetector based on RPP microwires (RPP-MWs) and compared it with a 2D-RPP photodetector. The results show that the RPP-MWs photodetector possesses a wider photoresponse range and higher responsivities of 233 A/W in the visible band and 30 A/W in the near-infrared (NIR) band. The analyses show that the synthesized RPP-MWs have a multi-layer, heterogeneous core-shell structure. This structure gives RPP-MWs a unique band structure, as well as abundant trap states and defect levels, which enable them to acquire better photoresponse performance. This configuration of RPP-MWs provides a new idea for the design and application of novel heterostructures.

由低维InAs材料和其他二维层状材料堆叠而成的垂直范德华异质结构在纳米电子、光电子和量子信息等新兴领域中应用广泛。探索跨结界面的电荷转移机制对于全面理解该类器件的非凡特性至关重要。第一性原理计算在揭示界面电荷转移特性与各种能量稳定型InAs基范德华异质结的电、光、磁等原理物理特性和器件性能变化之间的内在关系方面发挥着不可比拟的作用。文中梳理、总结和探讨了近年来InAs基范德华异质结间界面电荷转移特性的理论研究工作与潜在的功能应用，提出在理论方法和计算精度方面大力发展第一性原理计算的几个途径，为更好地开展InAs基范德华异质结的基础科学研究和应用器件设计提供可借鉴的量化研究基础。

我们报道了一种基于SnS₂ / InSe垂直异质结的宽带光电探测器，其光谱范围为365-965 nm。其中，InSe作为光吸收层，有效扩展了光谱范围，SnS₂作为传输层，与InSe形成异质结，促进了电子-空穴对的分离，增强了光响应。该光电探测器在 365 nm 下具有813 A/W 的响应度。并且，在965nm光照下它仍然具有371 A/W的高响应度，1.3×10⁵%的外量子效率，3.17×10¹² Jones的比探测率，以及27 ms的响应时间。该研究为高响应宽带光电探测器提供了一种新的方法。

A NiO/β-Ga₂O₃ heterojunction-gate field effect transistor (HJ-FET) is fabricated and its instability mechanisms are experimentally investigated under different gate stress voltage (V_G,s) and stress times (t_s). Two different degradation mechanisms of the devices under negative bias stress (NBS) are identified. At low V_G,s for a short t_s, NiO bulk traps trapping/de-trapping electrons are responsible for decrease/recovery of the leakage current, respectively. At higher V_G,s or long t_s, the device transfer characteristic curves and threshold voltage (V_TH) are almost permanently negatively shifted. This is because the interface dipoles are almost permanently ionized and neutralize the ionized charges in the space charge region (SCR) across the heterojunction interface, resulting in a narrowing SCR. This provides an important theoretical guide to study the reliability of NiO/β-Ga₂O₃ heterojunction devices in power electronic applications.

This work demonstrates high-performance NiO/β-Ga₂O₃ vertical heterojunction diodes (HJDs) with double-layer junction termination extension (DL-JTE) consisting of two p-typed NiO layers with varied lengths. The bottom 60-nm p-NiO layer fully covers the β-Ga₂O₃ wafer, while the geometry of the upper 60-nm p-NiO layer is 10 μm larger than the square anode electrode. Compared with a single-layer JTE, the electric field concentration is inhibited by double-layer JTE structure effectively, resulting in the breakdown voltage being improved from 2020 to 2830 V. Moreover, double p-typed NiO layers allow more holes into the Ga₂O₃ drift layer to reduce drift resistance. The specific on-resistance is reduced from 1.93 to 1.34 mΩ·cm². The device with DL-JTE shows a power figure-of-merit (PFOM) of 5.98 GW/cm², which is 2.8 times larger than that of the conventional single-layer JTE structure. These results indicate that the double-layer JTE structure provides a viable way of fabricating high-performance Ga₂O₃ HJDs.

采用修饰的高分子网络凝胶法成功制备了Mn₂O₃复合Mn掺杂ZnO纳米复合光催化剂（Mn：ZnO/Mn₂O₃），并基于模拟太阳光照射下罗丹明B（RhB）及亚甲基蓝（MB）染料的光降解研究了催化剂光催化降解有机染料的特性。X射线衍射，扫描电子显微镜及BET比表面积测试结果显示，微量（0.1 mol%）Mn掺杂再复合微量（0.2 mol%）Mn₂O₃后，Mn：ZnO/Mn₂O₃的颗粒尺寸减小且分散性提高，有效比表面积增大。紫外-可见光吸收光谱表明，相对于纯ZnO，Mn：ZnO/Mn₂O₃在可见光区域的光吸收能力明显提高。光致发光光谱表明微量Mn掺杂和微量Mn₂O₃复合促进了光生电子-空穴对的分离。结合X射线光电子能谱，发现可见光吸收能力和光生电子-空穴对分离率的提高源于催化剂表面氧空位的增加以及Mn：ZnO和Mn₂O₃之间形成的Ⅱ型异质结结构。因此，Mn：ZnO/Mn₂O₃对RhB的降解展现出稳定且优越的光催化活性。然而，由于Mn₂O₃的带隙（E_g≈1.4 eV）过窄，其价带位置高于羟基自由基（·OH）的氧化还原电位，因此光生空穴的氧化电势过低，无法生成氧化能力更强的·OH，这导致Mn₂O₃复合ZnO光催化剂（ZnO/Mn₂O₃）对RhB和MB的光降解效率降低。此外，Mn：ZnO/Mn₂O₃对RhB和MB展现出选择性光降解行为，即对容易降解的MB的光降解效率明显降低。这种选择性光催化特性归因于光催化反应过程中活性物种之间的差异性以及催化剂零电荷点和初始染料溶液的pH值之间的关系。

为实现有机光电探测器对三基色（红、绿、蓝）的全响应以及器件性能的改善，研究了在P3HT∶PCBM活性层中，掺入非富勒烯受体ITIC实现光谱拓宽以及通过改善迁移率的平衡性和活性层表面形态，进而改善探测器性能的方法，着重研究了ITIC受体含量对探测器光电学性能的影响。在此基础上，获得了一个覆盖400~800 nm波长范围的三基色探测器，并且在低偏压-1.5 V下三基色（波长为630、530和460 nm）的外量子效率EQE和比探测率D^*分别达到了56%、68%、52%和1.17×10¹² Jones、1.4×10¹² Jones、1.2×10¹² Jones。结果表明：在P3HT：PC₆₁BM中混入适量的ITIC，不仅可将光谱拓宽到400~800 nm，改善器件的光学特性，而且还可以提高激子解离率和载流子收集率，降低混合薄膜中的双分子复合，使器件电学特性得到了明显改善。本文研究为研发宽光谱高探测率三基色有机光电探测器提供了一种新思路。

基于500 nm 磷化铟双异质结双极晶体管（InP DHBT）工艺，设计了一种工作在33~170 GHz频段的超宽带共源共栅功率放大器。输入端和输出端的平行短截线起到变换阻抗和拓展带宽的作用，输出端紧密相邻的耦合传输线补偿了一部分高频传输损耗。测试结果表明，该放大器的最大增益在115 GHz达到11.98 dB，相对带宽为134.98%，增益平坦度为±2 dB，工作频段内增益均好于10 dB，输出功率均好于1 dBm。

Beta gallium oxide (β-Ga₂O₃) has attracted significant attention for applications in power electronics due to its ultra-wide bandgap of ~ 4.8 eV and the large critical electric field of 8 MV/cm. These properties yield a high Baliga’s figures of merit (BFOM) of more than 3000. Though β-Ga₂O₃ possesses superior material properties, the lack of p-type doping is the main obstacle that hinders the development of β-Ga₂O₃-based power devices for commercial use. Constructing heterojunctions by employing other p-type materials has been proven to be a feasible solution to this issue. Nickel oxide (NiO) is the most promising candidate due to its wide band gap of 3.6–4.0 eV. So far, remarkable progress has been made in NiO/β-Ga₂O₃ heterojunction power devices. This review aims to summarize recent advances in the construction, characterization, and device performance of the NiO/β-Ga₂O₃ heterojunction power devices. The crystallinity, band structure, and carrier transport property of the sputtered NiO/β-Ga₂O₃ heterojunctions are discussed. Various device architectures, including the NiO/β-Ga₂O₃ heterojunction pn diodes (HJDs), junction barrier Schottky (JBS) diodes, and junction field effect transistors (JFET), as well as the edge terminations and super-junctions based on the NiO/β-Ga₂O₃ heterojunction, are described.

二维材料中的新量子态对凝聚态物理和现代光电器件的发展具有重要意义。然而具有宽带、室温和快速响应能力的太赫兹光电探测技术，由于缺乏暗电流和光吸收之间的最佳平衡，仍然面临着巨大的挑战。在这项研究中，作者合成了新型拓扑绝缘体材料GeBi₄Te₇，并搭建了其与Bi₂Te₃的范德华异质结，以实现高灵敏度的太赫兹光电探测器。在平面金属-材料-金属结构中实现了在室温下将低光子能量太赫兹波段直接转化为光电流。结果表明，基于Bi₂Te₃-GeBi₄Te₇的太赫兹光电探测器能够实现0.02 ~0.54 THz的宽谱探测，且具有很高的光响应率（在 0.112、0.27、0.5 THz下分别为 592 V?W^-1、203 V?W^-1、40 V?W^-1），响应时间小于6 μs。值得注意的是，它被用于高频太赫兹的成像应用演示。这些结果为Bi₂Te₃-GeBi₄Te₇拓扑绝缘体异质结材料的低能量光电应用开辟了可行性途径。