State Key Laboratory of Material Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China.
Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, P. R. China.
Adv Mater. 2018 Dec;30(50):e1804541. doi: 10.1002/adma.201804541. Epub 2018 Oct 14.
Due to the intriguing anisotropic optical and electrical properties, low-symmetry 2D materials are attracting a lot of interest both for fundamental studies and fabricating novel electronic and optoelectronic devices. Identifying new promising low-symmetry 2D materials will be rewarding toward the evolution of nanoelectronics and nano-optoelectronics. In this work, germanium diarsenide (GeAs ), a group IV-V semiconductor with novel low-symmetry puckered structure, is introduced as a favorable highly anisotropic 2D material into the rapidly growing 2D family. The structural, vibrational, electrical, and optical in-plane anisotropy of GeAs is systematically investigated both theoretically and experimentally, combined with thickness-dependent studies. Polarization-sensitive photodetectors based on few-layer GeAs exhibit highly anisotropic photodetection behavior with lineally dichroic ratio up to ≈2. This work on GeAs will excite interests in the less exploited regime of group IV-V compounds.
由于其各向异性的光学和电学性质，低对称 2D 材料在基础研究和新型电子及光电设备的制造方面引起了广泛关注。寻找新的有前途的低对称 2D 材料将推动纳米电子学和纳光电学的发展。在这项工作中，我们引入了具有新颖低对称褶皱结构的 IV-V 族半导体锗砷化物（GeAs）作为一种很有前途的各向异性 2D 材料，加入到快速发展的 2D 材料家族中。我们通过理论和实验相结合的方法，对 GeAs 的结构、振动、电学和光学各向异性进行了系统研究，并结合厚度依赖性研究。基于少层 GeAs 的偏振敏感光电探测器表现出高度各向异性的光电探测行为，线性二色比高达约 2。这项关于 GeAs 的工作将激发人们对 IV-V 族化合物中较少被开发的领域的兴趣。
