Twist Angle-Dependent Metal-Insulator Transition in Twisted Bilayer PtTe₂

We investigate the electronic properties of twisted bilayer PtTe₂ using r2SCAN+rvv10, a method that closely aligns with quantum Monte Carlo (QMC) results. Our study reveals a twist-angle-dependent metal-insulator transition, marked by the opening of significant bandgaps. Interestingly, at the critical twist angle, only certain stacking regions in the moiré pattern exhibit metallic behavior, while other regions remain semiconducting. We demonstrate that in systems where the bandgap increases with decreasing layer thickness, twisting the upper layer near the metal-insulator transition can effectively modulate the bandgap. This finding suggests novel approaches for reducing metal-semiconductor contact resistance by fabricating junctions on the metallic facet of the moiré pattern. Our results offer fresh insights into “twistronics” and provide guidance for bandgap engineering and improving the performance of electronic devices.