Topological insulators have important potential for applications in the field of nano/micro-optoelectronic devices. However, the large dark current seriously hinders the improvement of device performance. Alloying is an important means to control the physical properties of topological insulators. In this work, we have designed and prepared Bi_1.3In_0.7Se₃ crystals. The optoelectronic properties of the individual Bi_1.3In_0.7Se₃ nanowire-based photodetector are systematically investigated. The photodetector is very sensitive to broadband wavelength from solar-blind ultraviolet C (254 nm) to near-infrared (1,064 nm), showing superior optoelectrical properties with photoresponsivity of 241.3 A·W⁻¹ and detectivity of 1.18 × 10¹² Jones at 638 nm. Furthermore, the photodetector demonstrates ultrafast photoresponse characteristics with a photoresponse time of about 770 ns, which is 3 to 6 orders of magnitude lower than other compound semiconductors based on Bi or In reported so far. In addition, it also exhibits good polarization sensitivity in a broadband range from ultraviolet C (266 nm) to near-infrared (1,064 nm) and obtained the maximum dichroic ratio is 1.73 at 1,064 nm. Our results suggest that this platform creates new opportunities for the development of low-cost, high-sensitivity, high-speed, and broadband angle-sensitive photodetectors.

拓扑绝缘体在纳米/微光电器件领域具有重要的应用潜力。然而，大的暗电流严重阻碍了器件性能的提高。合金化是控制拓扑绝缘体物理性能的重要手段。在这项工作中，我们设计并制备了Bi _1.3 In _0.7 Se ₃晶体。单个Bi _1.3 In _0.7 Se _{3的光电特性}系统地研究了基于纳米线的光电探测器。该光电探测器对从日盲紫外 C (254 nm) 到近红外 (1,064 nm) 的宽带波长非常敏感，显示出优异的光电特性，光响应度为 241.3 A·W ^-1，探测度为 1.18 × 10 ¹²琼斯在 638 nm。此外，该光电探测器表现出超快光响应特性，光响应时间约为 770 ns，比目前报道的基于 Bi 或 In 的其他化合物半导体低 3 至 6 个数量级。此外，它还在从紫外C（266 nm）到近红外（1,064 nm）的宽带范围内表现出良好的偏振灵敏度，并在1,064 nm处获得了最大二向色比为1.73。我们的研究结果表明，该平台为开发低成本、高灵敏度、高速和宽带角敏感光电探测器创造了新的机遇。