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Quantum anomalous Hall phase stabilized via realistic interactions on a kagome lattice

2018/06/28 by Yafei Ren, Tian-Sheng Zeng, T. -S. Zeng +2
Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Electron #Fermion #Lattice (music) #Physics #Quantum #Quantum Hall effect #Quantum anomalous Hall effect #Quantum many-body systems #Quantum mechanics #Quantum phase transition #Quantum phases #Topological Materials and Phenomena #cond-mat.str-el

paper · pdf · doi:10.1103/physrevb.98.205146

published as Phys. Rev. B 98, 205146 (2018) · 5 pages, 4 figures

arxiv created 2018/06/28 · openalex created_date 2018/07/10 · openalex publication_date 2018/11/26 · arxiv updated 2018/12/05 · openalex updated_date 2026/08/06

Abstract

We study the quantum phases of spinless fermions at one-third filling on a kagome lattice featuring a quadratic band touching Fermi point. In the presence of weak first and second nearest-neighbor repulsive interactions (V1 and V2), we demonstrate an interaction driven quantum anomalous Hall effect by employing exact diagonalization and density-matrix renormalization group methods. The time-reversal symmetry is broken spontaneously by forming loop currents that exhibit long-range correlation. Quantized Hall conductance corresponding to a Chern number of \ifmmode±\else\textpm\fi1 is obtained by measuring the pumped charge through inserting flux in a cylinder geometry. We find that the energy gap, which topologically protects the emerging ground states, can be enhanced remarkably by a moderate V2<V1 via calculating the spectrum and charge excitation gaps, which highlights the experimentally feasible scheme of realizing the interaction driven topological phase by spatially decaying interactions on topologically trivial lattice models.

Citations