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Self‐driven broadband photodetectors have wide applications in the fields of biomedicine, remote sensing, rescue, and mineral exploration with advantages of energy conservation and multiband detection. However, most present broadband photodetectors are suffering from a fast degradation of photoresponsivity in ultraviolet (UV) region. To resolve it, a self‐driven broadband photodetector is proposed based on mixed‐dimensional 2D PtSe2/3D amorphous Ga2O3 (a‐Ga2O3) heterojunction considering the high UV responsivity of a‐Ga2O3 thin film. 2D PtSe2 is obtained on a‐Ga2O3 thin film by a simple selenization method directly. The responsivity of the completed device in UV region is about 14 and 172 times higher than that in visible and NIR regions, respectively. In addition, benefiting from the excellent built‐in electric field at the heterojunction and high carrier mobility of 2D PtSe2, photogenerated electron–hole pairs can be rapidly separated. As a result, its rise time (9.36 ms) and decay time (11.27 ms) are much faster than those of the current a‐Ga2O3‐based self‐driven photodetectors (≈100–1000 ms). This work provides a novel building block via a facile strategy for the further development of high‐performance, low‐cost, and energy‐efficient broadband photodetectors. [ABSTRACT FROM AUTHOR]

Deep ultraviolet (UV) photodetectors have wide applications both in civil and military fields. Many materials have been explored to realize deep UV photodetection. Amorphous gallium oxide (a‐GaOx), as a member of transparent amorphous oxide semiconductors (TAOSs), has attracted a great deal of attention due to its ultrawide bandgap and scalable synthesis at room temperature. Plenty of researches have been focused on this topic in recent years. Herein, the latest progresses in the preparation methods of a‐GaOx using radio‐frequency sputtering, pulsed laser deposition, atomic layer deposition, and other deposition techniques are summarized. Dependence of the stoichiometry, crystallinity, optical, electrical, and morphological properties on different preparation parameters and doping/alloying elements is tentatively discussed, as well as those deep UV photodetectors based on a‐GaOx and related thin films. Finally, a short summary with further possible investigations is provided for a better understanding and development of a‐GaOx materials and photodetectors. [ABSTRACT FROM AUTHOR]

In this work, the optical properties of defects coupled with surface plasmons (SPs) in gallium‐doped ZnO (ZnO:Ga) grown by molecular beam epitaxy (MBE) have been explored. The photoluminescence intensity is enhanced by up to 4.9 times as a result of SPs coupling by decorating the sample with silver nanospheres (Ag NSs), with a fast plasmonic decay lifetime of 0.1 ns compared with the defect‐assisted carrier recombination lifetime of 3.77 ns in the as‐grown sample. The enhanced emission intensity depends on the plasmonic modes determined by the diameter of Ag NSs, verified by power‐dependent photoluminescence measurements. Confocal mapping reveals that the plasmonic “hot‐spots”, that is, enhanced emission around the Ag NSs, exhibit a highly optical stability with reduced photoluminescence blinking. This work demonstrates that a defect coupled with SPs in ZnO is a promising high‐efficiency emitter for applications in nanophotonics. [ABSTRACT FROM AUTHOR]