First-principle high-throughput calculations of carrier effective masses of two-dimensional transition metal dichalcogenides

Two-dimensional group-VIB transition metal dichalcogenides (with the formula of MX2) emerge as a family of intensely investigated semiconductors that are promising for both electronic (because of their reasonable carrier mobility) and optoelectronic (because of their direct band gap at monolayer thickness) applications. Effective mass is a crucial physical quantity determining carriers transport, and thus the performance of these applications. Here we present based on first-principles high-throughput calculations a computational study of carrier effective masses of the two-dimensional MX2 materials. Both electron and hole effective masses of different MX2 (M = Mo, W and X = S, Se, Te), including in-layer/out-of-layer components, thickness dependence, and magnitude variation in heterostructures, are systemically calculated. The numerical results, chemical trends, and the insights gained provide useful guidance for understanding the key factors controlling carrier effective masses in the MX2 system and further engineering the mass values to improve device performance.