Implementing electronic signatures of graphene and hexagonal boron nitride in twisted bilayer molybdenum disulfide
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<strong>Abstract</strong> Angeli and MacDonald reported a superlattice-imposed Dirac band in twisted bilayer molybdenum disulphide (tBL MoS2) for small twist angles towards the R_h^M (parallel) stacking. Using a hierarchical set of theoretical methods, we show that the superlattices differ for twist angles with respect to metastable R_h^M (0°) and lowest-energy H_h^h (60°) configurations. When approaching R_h^M stacking, identical domains with opposite spatial orientation emerge. They form a honeycomb superlattice, yielding Dirac bands and a lateral spin texture distribution with opposite-spin-occupied K and K’ valleys. Small twist angles towards the H_h^h configuration (60°) generate H_h^h and H_h^X stacking domains of different relative energies and, hence, different spatial extensions. This imposes a symmetry break in the moiré cell, which opens a gap between the two top-valence bands, which become flat already for relatively small moiré cells. The superlattices impose electronic superstructures resembling graphene and hexagonal boron nitride into trivial semiconductor MoS<sub>2</sub>. The data set published in this repository was used to create the preprint published at <strong>https://doi.org/10.26434/chemrxiv-2023-rx2fz</strong>. <strong>Content of repository</strong> "ReaxFF_structure_optimization.zip": contains the inputs and outputs for all structure optimizations for ML, BL, and tBL systems using the Reax force field, performed using LAMMPS. " bilayer_verification_ReaxFF_with_DFT.zip": contains the inputs and outputs for verifying the results of the Reax force field by running DFT geometry optimization and total energy calculations in FHI-aims for the high-symmetry bilayer stackings. "QATK_band_structures_and_eff_mass.zip": contains the inputs and outputs of all calculations done via QuantumATK (QATK), including calculations for ML, BL, and tBL systems on DFT and DFTB level of theory. "TB_fit.zip": contains the Python scripts and input data (DFTB band structure) used to fit the TB Hamiltonians as described in the Methods section and shown in the Supplementary Material. "effective_masses_from_bands.zip": contains the extraction of the effective hole masses from the bands calculated at the DFTB level of theory in QATK.



