Blackbody‐Sensitive Uncooled Infrared Detector with Ultra‐Broadband and Ultrafast Photoresponse Based on Te/WTe<sub>2</sub> Heterostructure
Yu Yu, Zhiyuan Dai, Haibiao Guan, Ruowen Wang, Ye Tao, Yonghao Bu, Jie Deng, Mengdie Shi, Liaoxin Sun, Rui Xin, Tianxin Li, Haibo Shu, Xiaoshuang Chen, Jing Zhou
Abstract
Abstract Blackbody‐sensitive uncooled infrared photodetectors with ultra‐broadband and ultrafast photoresponse have a profound impact on many areas of modern science and technology. However, it is a big challenge for both traditional photodetectors and emerging low‐dimensional ones to simultaneously have all the above characteristics. Here, this challenge is addressed by establishing a Te/WTe 2 heterostructure photodetector. The built‐in field of the heterostructure and the crossing conduction and valence bands of WTe 2 jointly result in a high responsivity and a visible‐to‐long‐wavelength‐infrared photoresponse range. The peak responsivity (at the 3.3 µm wavelength) reaches 914 mA W −1 at zero bias and 8.51 A W −1 at 2 V bias. Further, the joint action coupled with the high mobility of Te and WTe 2 promotes the 3‐dB bandwidth to 153 kHz. The self‐powered blackbody responsivity and specific detectivity reach 235.7 mA W −1 and 1.1 × 10 8 cm Hz 1/2 W −1 , respectively. The former increases to 5.82 A W −1 at 1 V bias. Moreover, this device is polarization‐sensitive with a contrast ratio of 2. This work reveals the potential of the Te/WTe 2 heterostructure for high‐performance room‐temperature infrared photodetectors.