Liu Yu, Hu Qianqian, Cao Yang, Wang Pengfei, Wei Jinquan, Wu Weidong, Wang Jian, Huang Feng, Sun Jia-Lin
College of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350108, China.
State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China.
ACS Appl Mater Interfaces. 2022 Jun 29;14(25):29077-29086. doi: 10.1021/acsami.2c03925. Epub 2022 Jun 13.
Ultrabroadband photodetectors (PDs) working in the frequency range from the UV to THz regions of the spectrum play a crucial role in integrated multifunction photoelectric detection. Even so, a shortage of high-performance PDs has seriously restricted the overall development of this field. The present work demonstrates a high-performance, ultrabroadband PD with a composite nanostructure comprising a suspended carbon nanotube (CNT) film on which titanium and palladium are deposited. The application of titanium and palladium to the CNT film in this device provides n-doping and p-doping, respectively, and the deposited metal nanoparticles also ensure enhanced thermal localization. This device exhibits short response time, high responsivity, large linear dynamic range, and small noise equivalent power over the ultrabroadband spectrum based on a strong photothermoelectric effect. Numerical simulation results also confirm the effective doping and enhanced thermal localization in this PD resulting from the deposited metals. A theoretical analysis shows that the thermal conductivity of the composite film is no longer independent of the temperature over a wide temperature range. This work provides a simple but novel strategy for the design of high-performance ultrabroadband PDs.
工作在从紫外到太赫兹光谱区域的超宽带光电探测器（PDs）在集成多功能光电探测中起着至关重要的作用。即便如此，高性能光电探测器的短缺严重限制了该领域的整体发展。目前的工作展示了一种具有复合纳米结构的高性能超宽带光电探测器，该结构包括一个悬浮的碳纳米管（CNT）薄膜，在其上沉积了钛和钯。在该器件中，将钛和钯应用于碳纳米管薄膜分别提供了n型掺杂和p型掺杂，并且沉积的金属纳米颗粒还确保了增强的热局域化。基于强烈的光热效应，该器件在超宽带光谱上表现出短响应时间、高响应度、大线性动态范围和小噪声等效功率。数值模拟结果也证实了该光电探测器中由于沉积金属而产生的有效掺杂和增强的热局域化。理论分析表明，在很宽的温度范围内，复合薄膜的热导率不再与温度无关。这项工作为高性能超宽带光电探测器的设计提供了一种简单但新颖的策略。
