Structural and electronic properties of twisted bilayer transition metal dichalcogenides from linear-scaling DFT

Recently, it has been proposed that Moiré superlattices of twisted homobilayer transition metal dichalcogenides (TMDs) exhibit many interesting structural and electronic properties, including shear solitons, phasons, topological point defects and ultraflatbands close to the Fermi level [1,2]. For small twist angles the unit cells of these systems contain thousands of atoms rendering first-principles investigations of their structural and electronic properties numerically challenging. To overcome this obstacle, we employ the linear-scaling DFT code ONETEP [3] and present results for relaxed geometries and band structures for both homo- and heterobilayers of transition metal dichalcogenides as function of twist angle.
[1] M. H. Naik and M. Jain, Phys. Rev. Lett. 121, 266401 (2018)
[2] I. Maity, M. H. Naik, P. K. Maiti, S. Ramaswamy, H. R. Krishnamurthy and M. Jain, arXiv:1905.11538 (2019)
[3] C.-K. Skylaris, P. D. Haynes, A. A. Mostofi and M. C. Payne, J. Chem. Phys. 122, 084119 (2005)