Quantum Phase Transitions in Graphene Coupled to a Twisted WSe ₂ Moiré Ferroelectricity

Sublattice symmetry in graphene governs its Dirac semimetal behavior, where electrons exhibit linear dispersion, limiting its potential for technological applications. Here, moiré ferroelectricity in twisted WSe₂ (t-WSe₂) is exploited to break graphene's sublattice symmetry, inducing a metal-to-insulator transition (MIT) near room temperature. The periodic polarization domains in t-WSe₂ imprint an electrostatic potential onto graphene, breaking its sublattice symmetry and leading to the emergence of a local Dirac point, as observed in the transfer characteristics of a t-WSe₂/graphene field-effect transistor. Temperature-dependent transport measurements reveal multiple MIT points at relatively high temperatures, attributed to the room-temperature ferroelectric polarization in t-WSe₂. Furthermore, A distinct metallic phases is identified exhibiting T² and linear-T dependent longitudinal resistance under electrostatic doping, indicative of Fermi-liquid and non-Fermi-liquid metallic behavior, respectively. Finally, finite-size scaling analysis of R_xx near the MIT points indicates continuous quantum phase transitions near room temperature, establishing moiré ferroelectricity as a pathway for engineering quantum electronic phases of monolayer graphene at ambient conditions.