Mechanical and electronic properties of mechanically-bent monolayer transition metal dichalcogenides (MX₂) in the ground state using SCAN density functional

As an alternative to graphene, transition metal dichalcogenides (TMD) have gained a lot of interest as promising candidates for future flexible nano-electronics due to the mechanical and electronic properties related to their high flexibility [1]. Though the TMD thin layers have a promising future, traditional methods of tuning the band gap such as doping with impurities or contact engineering suffer strong Fermi-level pinning or even damage the materials. However, due to the high bending and in-plane stiffness, thin monolayer MoS₂ can be bend mechanically to tune the bandgap as well as reducing Fermi level pinning to some extent [2]. In this work [3], we extend the study to exploring the other TMD monolayers corresponding to transition metals from groups IV to X in the periodic table in the ground state, using the recently developed meta-GGA SCAN.

[1] D. Akinwande, et al., Extreme Mechanics Letters 13, 42 (2017).

[2] L. Yu, A. Ruzsinszky, and J. P. Perdew, Nano Lett. 16, 2444 (2016).

[3] N. K. Nepal, et. al., Phys. Rev. Material 3 (7), 073601 (2019).