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arXiv · 1807.09457

Interplay between nematic fluctuation and superconductivity in the two-orbital Hubbard model: A quantum Monte Carlo study

Guangkun Liu·Shichao Fang·Xiaojun Zheng·Zhongbing Huang·Haiqing Lin
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Abstract

To understand the interplay between nematic fluctuation and superconductivity in iron-based superconductors, we performed a systematic study of the realistic two-orbital Hubbard model by using the constrained-path quantum Monte Carlo method. Our numerical results showed that the on-site nematic interaction induces a strong enhancement of nematic fluctuations at various momentums, especially at ($\pi$,$\pi$). Simultaneously, it was found that the on-site nematic interaction suppresses the ($\pi$,0)/(0,$\pi$) antiferromagnetic order and long-range electron pairing correlations for dominant pairing channels in iron-based superconductors. Our findings suggest that nematic fluctuation seems to compete with superconductivity in iron-based superconductors.

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Guangkun Liu, Shichao Fang, Xiaojun Zheng, Zhongbing Huang, Haiqing Lin. 2018-07-25. Interplay between nematic fluctuation and superconductivity in the two-orbital Hubbard model: A quantum Monte Carlo study. https://doi.org/10.1088/1361-648x/aae289

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