Quantum Phase Transitions in Graphene Coupled to a Twisted WSe<sub>2</sub> Moiré Ferroelectricity.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41122053.
- Also identified by DOI 10.1002/adma.202514744 and PMC identifier 12822538.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
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 WSe<sub>2</sub> (t-WSe<sub>2</sub>) is exploited to break graphene's sublattice symmetry, inducing a metal-to-insulator transition (MIT) near room temperature. The periodic polarization domains in t-WSe<sub>2</sub> 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-WSe<sub>2</sub>/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-WSe<sub>2</sub>. Furthermore, A distinct metallic phases is identified exhibiting T<sup>2</sup> 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<sub>xx</sub> 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.