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arXiv · 1109.6458

Pairing in graphene: A quantum Monte Carlo study

Tianxing Ma·Zhongbing Huang·Feiming Hu·Hai-Qing Lin
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Abstract

To address the issue of electron correlation driven superconductivity in graphene, we perform a systematic quantum Monte Carlo study of the pairing correlation in the t-U-V Hubbard model on a honeycomb lattice. For V=0 and close to half filling, we find that pairing with d+id symmetry dominates pairing with extended-s symmetry. However, as the system size or the on-site Coulomb interaction increases, the long-range part of the d+id pairing correlation decreases and tends to vanish in the thermodynamic limit. An inclusion of nearest-neighbor interaction V, either repulsive or attractive, has a small effect on the extended-s pairing correlation, but strongly suppresses the d+id pairing correlation.

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Tianxing Ma, Zhongbing Huang, Feiming Hu, Hai-Qing Lin. 2011-09-29. Pairing in graphene: A quantum Monte Carlo study. https://doi.org/10.1103/physrevb.84.121410

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