There is an urgent need for infrared (IR) detection systems with high-level miniaturization and room-temperature operation capability. The rising star of two-dimensional (2D) semimetals with extraordinary optoelectronic properties can fulfill these criteria. However, the formidable challenges with regard to large-scale patterning and substrate-selective requirements limit material deposition options for device fabrication. Here, we report a convenient and straightforward eutectic-tellurization transformation method for the wafer-level synthesis of 2D type-II Weyl semimetal WTe2. The non-cryogenic WTe2/Si Schottky junction device displays an ultrawide detection range covering 10.6 μm with a high detectivity of ∼109 Jones in the mid-infrared (MIR) region and a short response time of 1.3 μs. The detection performance has surpassed most reported IR sensors. On top of that, on-chip device arrays based on Schottky junction display an outstanding MIR imaging capability without cryogenic cooling, and 2D WTe2 Weyl semimetal can serve as a saturable absorber for stable Q-switched and mode-locked laser operation applications. Our work offers a viable route for wafer-scale vdW preparation of 2D semimetals, showcasing their intriguing potential in on-chip integrated MIR detection systems and ultrafast laser photonics.

中文翻译：

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基于晶圆级 Td-WTe2 Weyl 半金属的集成中红外传感和超短激光器


迫切需要具有高度小型化和室温操作能力的红外（IR）检测系统。具有非凡光电特性的二维 (2D) 半金属的后起之秀可以满足这些标准。然而，大规模图案化和基板选择性要求方面的巨大挑战限制了器件制造的材料沉积选择。在这里，我们报告了一种方便、直接的共晶碲化转化方法，用于晶圆级合成二维 II 型 Weyl 半金属 WTe2。非低温WTe2/Si肖特基结器件显示出覆盖10.6μm的超宽检测范围，在中红外（MIR）区域具有~109琼斯的高检测率和1.3μs的短响应时间。检测性能超过了大多数报道的红外传感器。最重要的是，基于肖特基结的片上器件阵列无需低温冷却即可表现出出色的中红外成像能力，而二维WTe2 Weyl半金属可以作为稳定调Q和锁模激光操作应用的可饱和吸收器。我们的工作为二维半金属的晶圆级 vdW 制备提供了一条可行的途径，展示了它们在片上集成 MIR 检测系统和超快激光光子学中的诱人潜力。