Jiang Hao, Fu Jintao, Wei Jingxuan, Li Shaojuan, Nie Changbin, Sun Feiying, Wu Qing Yang Steve, Liu Mingxiu, Dong Zhaogang, Wei Xingzhan, Gao Weibo, Qiu Cheng-Wei
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.
School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
Nat Commun. 2024 Feb 9;15(1):1225. doi: 10.1038/s41467-024-45498-3.
High quantum efficiency and wide-band detection capability are the major thrusts of infrared sensing technology. However, bulk materials with high efficiency have consistently encountered challenges in integration and operational complexity. Meanwhile, two-dimensional (2D) semimetal materials with unique zero-bandgap structures are constrained by the bottleneck of intrinsic quantum efficiency. Here, we report a near-mid infrared ultra-miniaturized graphene photodetector with configurable 2D potential well. The 2D potential well constructed by dielectric structures can spatially (laterally and vertically) produce a strong trapping force on the photogenerated carriers in graphene and inhibit their recombination, thereby improving the external quantum efficiency (EQE) and photogain of the device with wavelength-immunity, which enable a high responsivity of 0.2 A/W-38 A/W across a broad infrared detection band from 1.55 to 11 µm. Thereafter, a room-temperature detectivity approaching 1 × 10cm Hz W is obtained under blackbody radiation. Furthermore, a synergistic effect of electric and light field in the 2D potential well enables high-efficiency polarization-sensitive detection at tunable wavelengths. Our strategy opens up alternative possibilities for easy fabrication, high-performance and multifunctional infrared photodetectors.
高量子效率和宽带探测能力是红外传感技术的主要发展方向。然而，高效的块状材料在集成和操作复杂性方面一直面临挑战。与此同时，具有独特零带隙结构的二维（2D）半金属材料受到本征量子效率瓶颈的限制。在此，我们报道了一种具有可配置二维势阱的近中红外超小型石墨烯光电探测器。由介电结构构建的二维势阱可以在空间上（横向和纵向）对石墨烯中的光生载流子产生强大的俘获力，并抑制它们的复合，从而提高器件的外量子效率（EQE）和光增益，且具有波长免疫性，这使得在1.55至11μm的宽红外探测波段上具有0.2 A/W至38 A/W的高响应度。此后，在黑体辐射下获得了接近1×10cm Hz W的室温探测率。此外，二维势阱中电场和光场的协同效应使得在可调波长下能够进行高效的偏振敏感探测。我们的策略为易于制造、高性能和多功能红外光电探测器开辟了其他可能性。
