Integrating and manipulating the nano-optoelectronic properties of Van der Waals heterostructures can enable unprecedented platforms for photodetection and sensing. The main challenge of infrared photodetectors is to funnel the light into a small nanoscale active area and efficiently convert it into an electrical signal. Here, we overcome all of those challenges in one device, by efficient coupling of a plasmonic antenna to hyperbolic phonon-polaritons in hexagonal-BN to highly concentrate mid-infrared light into a graphene pn-junction. We balance the interplay of the absorption, electrical and thermal conductivity of graphene via the device geometry. This approach yields remarkable device performance featuring room temperature high sensitivity (NEP of 82 pW\(/\sqrt{{\bf{Hz}}}\)) and fast rise time of 17 nanoseconds (setup-limited), among others, hence achieving a combination currently not present in the state-of-the-art graphene and commercial mid-infrared detectors. We also develop a multiphysics model that shows very good quantitative agreement with our experimental results and reveals the different contributions to our photoresponse, thus paving the way for further improvement of these types of photodetectors even beyond mid-infrared range.

集成和操纵范德华异质结构的纳米光电特性可以为光电检测和传感提供前所未有的平台。红外光电探测器的主要挑战是将光聚集到一个小的纳米级活性区域并有效地将其转换为电信号。在这里，我们在一个设备中克服了所有这些挑战，通过将等离子体天线有效耦合到六边形 BN 中的双曲声子极化子，以将中红外光高度集中到石墨烯p n结中。我们通过器件几何形状平衡了石墨烯的吸收、导电和导热之间的相互作用。这种方法产生了卓越的器件性能，具有室温高灵敏度（NEP 为 82 pW \(/\sqrt{{\bf{Hz}}}\)) 和 17 纳秒的快速上升时间（设置受限）等，从而实现了目前在最先进的石墨烯和商用中红外探测器中不存在的组合。我们还开发了一个多物理场模型，该模型与我们的实验结果具有非常好的定量一致性，并揭示了对我们光响应的不同贡献，从而为进一步改进这些类型的光电探测器甚至超出中红外范围铺平了道路。