标题： 二维PN单层片材的奇妙结构和性能 显示英文标题

标题： Two-Dimensional PN Monolayer Sheets with Fantastic Structures and Properties

摘要： 三种二维磷氮化物（PN）单层片材（分别命名为$\alpha$-、$\beta$-和$\gamma$-PN）基于第一性原理计算被预测具有非凡的结构和性能。 $\alpha$-PN 和$\gamma$-PN 具有波纹结构，而$\beta$-PN 表现出波浪状特征。 它们独特的结构赋予这些原子级 PN 片材高动态稳定性和各向异性力学性能。 它们都是间接半导体，其带隙对平面内应变非常敏感。 此外，从这三种 PN 单层片材中图案化的纳米带表现出显著的量子尺寸效应。 特别是，锯齿形$\alpha$-PN 纳米带表现出尺寸依赖的铁磁性。 它们显著的性能在纳米电子学中具有潜力。 提出了三种 PN 单层片材相的合成理论，这值得在实验中进一步研究。 显示英文摘要

摘要： Three two-dimensional phosphorus nitride (PN) monolayer sheets (named as $\alpha$-, $\beta$-, and $\gamma$-PN, respectively) with fantastic structures and properties are predicted based on first-principles calculations. The $\alpha$-PN and $\gamma$-PN are buckled structure, whereas $\beta$-PN shows puckered characteristics. Their unique structures endows these atomic PN sheets with high dynamic stabilities and anisotropic mechanical properties. They are all indirect semiconductors and their band gap sensitively depends on the in-plane strain. Moreover, the nanoribbons patterned from these three PN monolayers demonstrate remarkable quantum size effect. Particularly, the Zigzag $\alpha$-PN nanoribbon shows size-dependent ferromagnetism. Their significant properties show potential in nano-electronics. The synthesis of the three phases of PN monolayer sheets is proposed theoretically, which is deserved to further study in experiments.