Chen Po-Liang, Chen Yueyang, Chang Tian-Yun, Li Wei-Qing, Li Jia-Xin, Lee Seokhyeong, Fang Zhuoran, Li Mo, Majumdar Arka, Liu Chang-Hua
Institute of Photonics Technologies, National Tsing Hua University, Hsinchu 30013, Taiwan.
Department of Electrical and Computer Engineering, University of Washington, Seattle, Washington 98195, United States.
ACS Appl Mater Interfaces. 2022 Jun 1;14(21):24856-24863. doi: 10.1021/acsami.2c01094. Epub 2022 Apr 27.
Extending the operation wavelength of silicon photonics to the mid-infrared (mid-IR) band will significantly benefit critical application areas, including health care, astronomy, and chemical sensing. However, a major hurdle for mid-IR silicon photonics has been the lack of high-speed, high-responsivity, and low noise-equivalent power (NEP) photodetectors. Here, we demonstrate a van der Waals (vdW) heterostructure mid-IR photodetector integrated on a silicon-on-insulator (SOI) waveguide. The detector is composed of vertically stacked black phosphorus (BP)/molybdenum ditelluride (MoTe). We measured high responsivity (up to 0.85 A/W) over a 3-4 μm spectral range, indicating that waveguide-confined light could strongly interact with vdW heterostructures on top. In addition, the waveguide-integrated detector could be modulated at high speed (>10 MHz) and its switching performance shows excellent stability. These results, together with the noise analysis, indicate that the NEP of the detector is as low as 8.2 pW/Hz. This reported critical missing piece in the silicon photonic toolbox will enable the wide-spread adoption of mid-IR integrated photonic circuits.
将硅光子学的工作波长扩展到中红外（mid-IR）波段将极大地惠及包括医疗保健、天文学和化学传感在内的关键应用领域。然而，中红外硅光子学的一个主要障碍一直是缺乏高速、高响应度和低噪声等效功率（NEP）的光电探测器。在此，我们展示了一种集成在绝缘体上硅（SOI）波导上的范德华（vdW）异质结构中红外光电探测器。该探测器由垂直堆叠的黑磷（BP）/二碲化钼（MoTe）组成。我们在3 - 4μm光谱范围内测量到了高响应度（高达0.85 A/W），这表明波导限制的光可以与顶部的vdW异质结构强烈相互作用。此外，集成在波导上的探测器可以高速（>10 MHz）调制，并且其开关性能显示出优异的稳定性。这些结果，连同噪声分析表明，该探测器的NEP低至8.2 pW/Hz。这一在硅光子工具箱中报道的关键缺失部件将使中红外集成光子电路得到广泛应用。
