Tunable Electronic Properties of Multilayer Talc: Combined First-Principles and Experimental Insights

We present a comprehensive theoretical study of the electronic properties of multilayer two-dimensional talc under a perpendicular electric field. Using first-principles density functional theory, we analyze multiple stacking configurations, examining equilibrium geometries, interlayer binding energies, band structures, and projected densities of states. Among the configurations studied, AA stacking is identified as the most stable, consistent with experimental lattice parameters. The band gap remains direct up to four layers, even under external fields. It decreases with increasing thickness, approaching the bulk limit. Charge localization analysis reveals the formation of quantized states with quantum well-like profiles. We also evaluate the effective mass tensor and its variation across the Brillouin zone. Our results demonstrate a tunable semiconductor-to-metal transition, with the critical field decreasing as the number of layers increases and varying across stackings. Finally, theoretical predictions are compared with experimental dielectric breakdown measurements, highlighting the potential of talc as a gate dielectric in van der Waals heterostructures.