Tunable edge states of nanoribbons by density functional theory and GW approximations*

2D layered materials belong to a rapidly growing area in material science and technology, due to their amazing properties and promising applications in fields of energy recovery,storage, catalysts, next-generation electronics, optoelectronics. Their properties are tunable via configurations, strain, and bending. Previous studies [1,2] by PBE and SCAN functionals showed that under mechanical bending, some TMD monolayer nanoribbons undergo high nonuniform local strain within the curved layers, much larger than uni-axial strain, making band edge states more tunable in these 2D materials. It helps to remove the strong Fermi-level pinning in the flat states, making the materials usable in contact-engineering [1,2]. Many-body GW approximations can provide accurate band structures for solid materials. We use GW calculations to check the tunability of the band edges of MoS2 nanoribbon with various widths. To make the GW computation manageable, the static Coulomb-hole remainder correction will be considered. The results will be compared with that from modified meta-GGA semilocal density functionals.

[1] L.Yu, A. Ruzsinszky, J. P. Perdew, Nano Lett. 2016,16,2444
[2] N.K.Nepal, L.Yu, Q.Yan, A. Ruzsinszky, Phy. Rev. MAT. 2019,3,073601