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arXiv · 2106.04395

Low-energy effective theory and symmetry classification of flux phases on Kagome lattice

Xilin Feng·Yi Zhang·Kun Jiang·Jiangping Hu
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Abstract

Motivated by recent experiments on AV$_3$Sb$_5$ (A=K,Rb,Cs), the chiral flux phase has been proposed to explain time-reversal symmetry breaking. To fully understand the physics behind the chiral flux phase, we construct a low-energy effective theory based on the van-Hove points around the Fermi surface. The possible symmetry-breaking states and their classifications of the low-energy effective theory are completely studied, especially the flux phases on Kagome lattice. In addition, we discuss the relations between the low-energy symmetry breaking orders, the chiral flux and charge bond orders. We find all possible 183 flux phases on Kagome lattice within 2*2 unit cell by brute-force approach and classify them by point group symmetry. Among the 183 phases, we find 3 classes in 1*1 unit cell, 8 classes in 1*2 unit cell and 18 classes in 2*2 unit cell, respectively. These results provide a full picture of the time-reversal symmetry breaking in Kagome lattices.

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Xilin Feng, Yi Zhang, Kun Jiang, Jiangping Hu. 2021-10-14. Low-energy effective theory and symmetry classification of flux phases on Kagome lattice. https://doi.org/10.1103/physrevb.104.165136

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