Group IV–V 2D semiconductors, such as GeP and GeAs, have attracted increasing attention as a hot research topic due to their high in-plane anisotropic properties. As one among them, orthorhombic SiP (o-SiP) deserves more attention due to its sufficiently high carrier mobility, large band gap, excellent stability and even a direct band gap in the monolayer. In this work, the experimental Raman modes were identified based on DFT calculations and then we demonstrated highly in-plane anisotropy of the phonon vibrations by angle-resolved polarized Raman spectroscopy. In addition, o-SiP based photodetectors were fabricated to investigate the in-plane anisotropic photoresponse. The results indicate that o-SiP is an alternative photodetector with high responsivity and well-reproducible cycles. Furthermore, high anisotropy was revealed with a notably anisotropic on/off switching ratio. Our results show that o-SiP is a new member of the family of group IV–V 2D semiconductors with intriguing optoelectronic properties, and will open new opportunities for promising applications in advanced photonic and optoelectronic devices.

中文翻译：

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使用新的IV–V 2D组正交晶SiP †对偏振光进行高灵敏检测

诸如GeP和GeAs之类的IV–V 2D组半导体由于其高的面内各向异性特性而引起了越来越多的关注，成为一个热门研究课题。作为其中之一，正交晶SiP（o-SiP）由于其足够高的载流子迁移率，大的带隙，出色的稳定性甚至单层中的直接带隙而值得关注。在这项工作中，基于DFT计算确定了实验拉曼模式，然后我们通过角度分辨偏振拉曼光谱证明了声子振动的高度面内各向异性。此外，制造了基于o-SiP的光电探测器以研究面内各向异性光响应。结果表明，o-SiP是具有高响应度和良好可重复周期的替代光电探测器。此外，高各向异性表现出明显的各向异性开/关切换比。我们的结果表明，o-SiP是具有诱人的光电特性的IV–V 2D组半导体家族的新成员，它将为先进的光子和光电器件的有希望的应用打开新的机遇。