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arXiv · 2106.15573

Band Structure and Superconductivity in Twisted Trilayer Graphene

Vo Tien Phong·Pierre A. Pantaleón·Tommaso Cea·Francisco Guinea
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Abstract

We study the symmetries of twisted trilayer graphene's band structure under various extrinsic perturbations, and analyze the role of long-range electron-electron interactions near the first magic angle. The electronic structure is modified by these interactions in a similar way to twisted bilayer graphene. We analyze electron pairing due to long-wavelength charge fluctuations, which are coupled among themselves via the Coulomb interaction and additionally mediated by longitudinal acoustic phonons. We find superconducting phases with either spin singlet/valley triplet or spin triplet/valley singlet symmetry, with critical temperatures of up to a few Kelvin for realistic choices of parameters.

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Vo Tien Phong, Pierre A. Pantaleón, Tommaso Cea, Francisco Guinea. 2021-06-29. Band Structure and Superconductivity in Twisted Trilayer Graphene. https://doi.org/10.1103/physrevb.104.l121116

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