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arXiv · 1706.07087

Emergent phases in iron pnictides: Double-Q antiferromagnetism, charge order and enhanced nematic correlations

Rong Yu·Ming Yi·Benjamin A. Frandsen·Robert J. Birgeneau·Qimiao Si
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Abstract

Electron correlations produce a rich phase diagram in the iron pnictides. Earlier theoretical studies on the correlation effect demonstrated how quantum fluctuations weaken and concurrently suppress a $C_2$-symmetric single-Q antiferromagnetic order and a nematic order. Here we examine the emergent phases near the quantum phase transition. For a $C_4$-symmetric collinear double-Q antiferromagnetic order, we show that it is accompanied by both a charge order and an enhanced nematic susceptibility. Our results provide understanding for several intriguing recent experiments in hole-doped iron arsenides, and bring out common physics that underlies the different magnetic phases of various iron-based superconductors.

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Rong Yu, Ming Yi, Benjamin A. Frandsen, Robert J. Birgeneau, Qimiao Si. 2017-06-21. Emergent phases in iron pnictides: Double-Q antiferromagnetism, charge order and enhanced nematic correlations. https://arxiv.org/abs/1706.07087

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