Abstract Electric field (E-field) effects on electric and optical properties of α-, β- and δ-SnSe have been investigated. Under the E-field, a tunable band gap of δ-SnSe appears, ranging from 2.23 to 1.26 eV. The band gap of β-SnSe could be mildly regulated by the E-field, just from 2.32 to 2.01 eV. For α-SnSe, the E-field has little effect on its band gap. We further find that the Sn-p and Se-p states mainly contribute to the variations of the band structures. Moreover, due to the application of the E-field, the absorption strength of α-SnSe in visible light might be enhanced.

中文翻译：

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电场对 SnSe 电子和光学特性的影响：第一性原理研究

摘要 已经研究了电场 (E-field) 对 α-、β- 和 δ-SnSe 的电学和光学性质的影响。在电场下，δ-SnSe 的可调带隙出现，范围从 2.23 到 1.26 eV。β-SnSe 的带隙可以通过 E 场温和调节，仅从 2.32 到 2.01 eV。对于 α-SnSe，电场对其带隙几乎没有影响。我们进一步发现 Sn-p 和 Se-p 状态主要有助于能带结构的变化。此外，由于电场的应用，α-SnSe 在可见光中的吸收强度可能会增强。