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arXiv · 2106.13231

Acoustic-phonon-mediated superconductivity in rhombohedral trilayer graphene

Yang-Zhi Chou·Fengcheng Wu·Jay D. Sau·Sankar Das Sarma
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Abstract

Motivated by the observation of two distinct superconducting phases in the moiréless ABC-stacked rhombohedral trilayer graphene, we investigate the electron-acoustic-phonon coupling as a possible pairing mechanism. We predict the existence of superconductivity with the highest $T_c\sim 3$K near the Van Hove singularity. Away from the Van Hove singularity, $T_c$ remains finite in a wide range of doping. In our model, the $s$-wave spin-singlet and $f$-wave spin-triplet pairings yield the same $T_c$, while other pairing states have negligible $T_c$. Our theory provides a simple explanation for the two distinct superconducting phases in the experiment and suggests that superconductivity and other interaction-driven phases (e.g., ferromagnetism) can have different origins.

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Yang-Zhi Chou, Fengcheng Wu, Jay D. Sau, Sankar Das Sarma. 2021-10-25. Acoustic-phonon-mediated superconductivity in rhombohedral trilayer graphene. https://doi.org/10.1103/physrevlett.127.187001

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