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 (Cd 3 As 2 ) has ultra-high charge mobility beyond graphene and possess strong light and matter interaction. Herein, photodetector prototype based on micro-nanometer scaled Cd 3 As 2 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 Cd 3 As 2 /CuPc heterojunction was further introduced for suppress dark current of Dirac semimetal Cd 3 A 2 nanobelt that would effectively improve photoelectric detection performance. As expected, the responsivity ( R ) of Cd 3 As 2 /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 × 10 10 Jones under irradiation of 808 nm laser, respectively. All of the results indicate that 3D Dirac semi-metal Cd 3 As 2 and its heterojunction design are great prospect applied in high-performance broadband detection devices. • The high-performance photodetector of Dirac semimetal Cd 3 As 2 nano-belt and heterojunction of Cd 3 As 2 /CuPc were developed and investigated. • The introduction of CuPc is conducive to reducing the dark current of Cd 3 As 2 and improving device performance. • Enhanced performance of Cd 3 As 2 /CuPc is benefited from the reduced noise and improved photoelectric conversion efficiency.