3D Dirac semimetal Cd3As2/CuPc heterojunction for promoted visible-infrared photo-detection

Abstract Recently, discovery of three-dimensional (3D) topological Dirac/Weyl semi-metal opens up a new frontier fields for neoteric type of photodetectors. As a most representative 3D Dirac semi-metal, Cadmium arsenide (Cd3As2) has ultra-high charge mobility beyond graphene and possess strong light and matter interaction. Herein, photodetector prototype based on micro-nanometer scaled Cd3As2 was developed, which has high photocurrent response even under slight bias of 1 mV and its responsivity could be up to 4.65 A/W at near infrared waveband of 808 nm. Moreover, the Cd3As2/CuPc heterojunction was further introduced for suppress dark current of Dirac semimetal Cd3A2 nanobelt that would effectively improve photoelectric detection performance. As expected, the responsivity (R) of Cd3As2/CuPc has been significantly enhanced in visible (405 nm) to near-infrared (980 nm) region, and maximum R and optimal detectivity (D*) of detector can be reach about 142.5 A/W and 7.83 × 1010 Jones under irradiation of 808 nm laser, respectively. All of the results indicate that 3D Dirac semi-metal Cd3As2 and its heterojunction design are great prospect applied in high-performance broadband detection devices.