APS Logo

Electron-phonon coupling and superconductivity in rhombohedral trilayer graphene

ORAL

Abstract

A recent experiment shows the rhombohedral phase of trilayer graphene manifesting superconducting behavior at low temperature. With electric field and doping introduced, the rhombohedral trilayer graphene sample shows vanishing resistivity under sub-kelvin temperature. However, a good understanding of the mechanism behind this phenomenon is still lacking. In this work, we first perform ab initio DFT calculations to address the role of electron-phonon coupling in the superconductivity of rhombohedral trilayer graphene using density functional perturbation theory (DFPT). The electron-phonon coupling strength may be used to estimate the superconducting transition temperature. To include the effects of many-body interactions, we next perform GW perturbation theory (GWPT) calculations to obtain electron-phonon coupling matrix elements that include the GW self-energy.  Any change in the matrix elements would affect the electron-phonon coupling strength, which has been shown to be quite large in some correlated systems, and thus would modify the superconducting transition temperature.

–

Presenters

  • Jingwei Jiang

    Physics Department, UC Berkeley and Lawrence Berkeley National Lab

Authors

  • Jingwei Jiang

    Physics Department, UC Berkeley and Lawrence Berkeley National Lab

  • Zhenglu Li

    University of California at Berkeley, and Lawrence Berkeley National Laboratory, Physics Department, UC Berkeley and Lawrence Berkeley National Lab, Lawrence Berkeley National Laboratory, Lawrence Berkeley National Laboratory; University of California at Berkeley, University of California at Berkeley and Lawrence Berkeley National Laboratory

  • Steven G Louie

    University of California at Berkeley, and Lawrence Berkeley National Laboratory, Physics Department, UC Berkeley and Lawrence Berkeley National Lab, University of California Berkeley, University of California, Berkeley, University of California at Berkeley; Lawrence Berkeley National Laboratory, University of California at Berkeley and Lawrence Berkeley National Laboratory, UC berkeley, University of California at Berkeley and Lawrence Berkeley National Lab, UC Berkeley & Lawrence Berkeley National Laboratory