Effects Of Electric Field On Electronic And Optical Properties Of Snse: A First-Principle Study

Electric field (E-field) effects on electric and optical properties of alpha-, beta- and delta-SnSe have been investigated. Under the E-field, a tunable band gap of delta-SnSe appears, ranging from 2.23 to 1.26 eV. The band gap of beta-SnSe could be mildly regulated by the E-field, just from 2.32 to 2.01 eV. For alpha-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 alpha-SnSe in visible light might be enhanced.