Abstract Two-dimensional (2D) polyaniline with C3N stoichiometry, is a newly fabricated layered material that has been expected to possess fascinating electronic, thermal, mechanical and chemical properties. The nature of its counterpart nanoribbons offering even more tunability in properties because of the unique quantum confinement and edge effect, however, has not been revealed yet. Here we systemically study the mechanical, electronic and magnetic properties for various nanoribbons cutting from a monolayer C3N sheet along the typical crystallographic orientations. By the first-principles calculations we find that C3N nanoribbons exhibit sensitive responses to the externally applied electric field and strain. Specifically, the spin-selective half-metallicity depends on the external electric field or strain, as well as the ribbon width. For the asymmetric zigzag-edged ribbon, the spin-polarization rate approaches −100% at electric field strength −0.2 V/A. Interestingly, an applied strain can transform a symmetric zigzag-carbon-edge ribbon from a magnetic semiconductor to a half-metal. And the half-metal property remains unchanged when the strain increases from 8 to 15%, while the spin-up subband gap further increases to 0.46 eV. These numerical results may be useful to engineer and design magnetic-field-free spintronic devices based on the 2D C3N.

中文翻译：

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通过外场可调节单层 C3N 纳米带的机械、电子和磁性能

摘要 具有 C3N 化学计量的二维 (2D) 聚苯胺是一种新制造的层状材料，预计具有迷人的电子、热、机械和化学性能。然而，由于独特的量子限制和边缘效应，其对应纳米带的性质在特性上提供了更多的可调性，但尚未揭示。在这里，我们系统地研究了沿典型晶体取向从单层 C3N 片切割的各种纳米带的机械、电子和磁性能。通过第一性原理计算，我们发现 C3N 纳米带对外部施加的电场和应变表现出敏感的响应。具体而言，自旋选择性半金属性取决于外部电场或应变，以及带宽度。对于不对称的锯齿形边缘带，自旋极化率在电场强度为 -0.2 V/A 时接近 -100%。有趣的是，施加的应变可以将对称的锯齿形碳边带从磁性半导体转变为半金属。当应变从 8% 增加到 15% 时，半金属特性保持不变，而自旋子带隙进一步增加到 0.46 eV。这些数值结果可能有助于设计和设计基于 2D C3N 的无磁场自旋电子器件。而自旋子带隙进一步增加到 0.46 eV。这些数值结果可能有助于设计和设计基于 2D C3N 的无磁场自旋电子器件。而自旋子带隙进一步增加到 0.46 eV。这些数值结果可能有助于设计和设计基于 2D C3N 的无磁场自旋电子器件。