The distinguished electronic and optical properties of lead halide perovskites (LHPs) make them good candidates for active layer in optoelectronic devices. Integrating LHPs and two-dimensional (2D) transition metal dichalcogenides (TMDs) provides opportunities for achieving increased performance in heterostructured LHPs/TMDs based optoelectronic devices. The electronic structures of LHPs/TMDs heterostructures, such as the band offsets and interfacial interaction, are of fundamental and technological interest. Here CsPbBr₃ and MoSe₂ are taken as prototypes of LHPs and 2D TMDs to investigate the band alignment and interfacial coupling between them. Our GGA-PBE and HSE06 calculations reveal an intrinsic type-II band alignment between CsPbBr₃ and MoSe₂. This type-II band alignment suggests that the performance of CsPbBr₃-based photodetectors can be improved by incorporating MoSe₂ monolayer. Furthermore, the absence of deep defect states at CsPbBr₃/MoSe₂ interfaces is also beneficial to the better performance of photodetectors based on CsPbBr₃/MoSe₂ heterostructure. This work not only offers insights into the improved performance of photodetectors based on LHPs/TMDs heterostructures but it also provides guidelines for designing high-efficiency optoelectronic devices based on LHPs/TMDs heterostructures.

为分析2 m环形地基太阳望远镜系统的杂散光，对该系统光机结构进行杂散光仿真模拟。基于Tracepro软件建立2 m环形地基太阳望远镜系统的光机模型，对光机组件进行光线追迹，着重分析了系统主镜、次镜、光阑面、主镜室前表面以及桁架等组件一次散射，使用点源透过率计算方法得到系统点源透过率（PST）曲线。结果表明，当离轴角θ≥5′时，系统PST≤1.728×10^?4，2 m环形地基太阳望远镜可以较好地满足对太阳磁场高分辨率成像的需求，系统观测不会受到杂散光的影响。

The photoelectric properties of conductive films are improved by doping Ag on aluminum-doped zinc oxide (AZO) films by laser induced forward transfer (LIFT). Firstly, the picosecond laser induced transfer mechanism of Ag films was revealed by numerical simulation; then, different-thickness Ag films were deposited on the AZO films by picosecond LIFT. When the film thickness is 30 nm and 50 nm, we have successfully obtained some Ag-AZO films with better optoelectronic properties by adjusting the laser parameters.

The novel vertically standing PtSe2 film on transparent quartz was prepared by selenization of platinum film deposited by the magnetron sputtering method, and an Nd:LuVO4 passively mode-locked solid-state laser was realized by using the fabricated PtSe2 film as a saturable absorber. The X-ray diffraction pattern and Raman spectrum of the film indicate its good crystallinity with a layered structure. The thickness of PtSe2 film is measured to be 24 nm according to the cross-section height profile of the atomic force microscope image. High-resolution transmission electron microscopy images clearly demonstrate its vertically standing structure with an interlayer distance of 0.54 nm along the c-axis direction. The modulation depth (ΔT) and saturation fluence ( s) of PtSe2 film are measured to be 12.6% and 17.1 μJ/cm2, respectively. The obtained mode-locked laser spectrum has a central wavelength of 1066.573 nm, with a 3 dB bandwidth of 0.106 nm. The transform limited pulse width of the mode-locked laser was calculated to be 15.8 ps. A maximum average output power of 180 mW with a working repetition rate of 61.3 MHz is obtained. To the best of our knowledge, this is the first report of the generation of ultrafast mode-locked laser pulses by using layered PtSe2 as a saturable absorber.