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arXiv · 2003.02403

Lifshitz Transition in Triangular Lattice Kondo-Heisenberg Model

Lan Zhang·Hong-Gang Luo·Yin Zhong
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Abstract

Motivated by recent experimental progress on triangular lattice heavy-fermion compounds, we investigate possible Lifshitz transitions and the scanning tunnel microscope (STM) spectra of the Kondo-Heisenberg model on the triangular lattice. In the heavy Fermi liquid state, the introduced Heisenberg antiferromagnetic interaction ($J_H$) results in the twice Lifshitz transition at the case of the nearest-neighbour electron hopping but with next-nearest-neighbour hole hopping and the case of the nearest-neighbour hole hopping but with next-nearest-neighbour electron hopping, respectively. Driven by $J_H$, the Lifshitz transitions on triangular lattice are all continuous in contrast to the case in square lattice. Furthermore, the STM spectra shows rich line-shape which is influenced by the Kondo coupling $J_{K}$, $J_{H}$ and the ratio of the tunneling amplitude $t_{f}$ versus $t_{c}$. Our work provides a possible scenario to understand the Fermi surface topology and the quantum critical point in heavy-fermion compounds.

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Lan Zhang, Hong-Gang Luo, Yin Zhong. 2020-03-05. Lifshitz Transition in Triangular Lattice Kondo-Heisenberg Model. https://doi.org/10.1088/1674-1056/ab8da4

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