Thickness-Controlled Three-Dimensional Dirac Semimetal for Scalable High-Performance Terahertz Optoelectronics

作者：Xiaomei Yao, Shengxi Zhang, Qiang Sun, Peizong Chen, Peizong Chen, Xutao Zhang, Libo Zhang, Jian Zhang, Yan Wu, Jin Zou, Pingping Chen, Pingping Chen, Lin Wang · 发表于：ACS Photonics · 年份：2021 · DOI：10.1021/acsphotonics.1c00127 · 被引用次数：31 · 研究领域：Topological Materials and Phenomena、2D Materials and Applications、Metamaterials and Metasurfaces Applications

The advent of topological semimetals with peculiar band structure and exotic transport provides an unprecedented material platform that allows exploring novel optoelectronics for circumventing technological bottlenecks. Cd 3 As 2, a three-dimensional Dirac semimetal, represents a hallmark system for studying nontrivial quantum phenomena led by Dirac/Weyl physics. However, controllable growth and device implementation are still in their infancy due to lack of efficient ways to make use of light-induced effects in semimetals. In this study, highly sensitive, low-energy photodetection up to terahertz (THz) band wavelength along with fast response at room temperature has been implemented in an antenna-assisted Cd 3 As 2 planar structure, which is derived from molecular-beam epitaxial growth. It is demonstrated that the THz photodetector based on semimetal Cd 3 As 2 films possesses a responsivity of 0.04 A/W and a NEP value of 430 pW/Hz 1/2 . Nonequilibrium manipulation of Dirac fermions with thickness-controlled gap phases and an electromagnetic-coupling effect has been well exploited. Our results portray opportunities for developing high-performance, scalable low-energy photodetectors enabled by a Dirac semimetal, which is promising for broadband photoresponses in the highly pursued THz band.