Ultraviolet to Long-Wave Infrared Photodetectors Based on a Three-Dimensional Dirac Semimetal/Organic Thin Film Heterojunction

作者：Yang, Ming; Wang, Jun^*; Yang, Yunkun; Zhang, Qi; Ji, Chunhui; Wu, Guorong; Su, Yuanjie; Gou, Jun; Wu, Zhiming; Yuan, Kaijun; Xiu, Faxian^*; Jiang, Yadong

来源：Journal of Physical Chemistry Letters, 2019, 10(14): 3914-3921.

DOI：10.1021/acs.jpclett.9b01619

• GRAPHENE
• PERFORMANCE
• HETEROSTRUCTURES
• 2D

In this work, high-performance ultraviolet to long-wave infrared (UV-LIR) devices based on an N-type three-dimensional (3D) Dirac semimetal Cd3As2 and P-type organic (small molecules and polymers) heterojunction are prepared. Primarily, the photodetector shows a broadband photoresponse from 365 to 10600 nm. The optimized device responsivity is 729 mA/W, along with a fast response time of 282 its and a high on-off ratio of 6268, which are 2 orders of magnitude higher than those previously reported for a 3D Dirac semimetal-based device. In the LIR region (10600 nm), the responsivity and on-off ratio can reach 81.3 mA/W and 100, respectively. In addition, the time-resolved femtosecond pump detection technology is used to reveal the relaxation time of Cd3As2/organic thin films (4.30 ps), indicating that Cd3As2/organic thin films have great potential for the manufacture of fast IR devices. These results demonstrate that the 3D Dirac semimetal/organic thin film heterojunction photo detectors will be a feasible solution for high-speed and broadband photodetectors in large-array imaging.

• 单位
  电子科技大学; 中国科学院大连化学物理研究所; 复旦大学