Inspired by the recent discovery of breathing kagome materials Nb_(3)Cl_(8) and Nb_(3)TeCl_(7),we have explored the influence of the breathing effect on the Hubbard model of the kagome lattice.Utilizing the determinan...Inspired by the recent discovery of breathing kagome materials Nb_(3)Cl_(8) and Nb_(3)TeCl_(7),we have explored the influence of the breathing effect on the Hubbard model of the kagome lattice.Utilizing the determinant quantum Monte Carlo method,we first investigated the average sign problem in the breathing kagome lattice,which is influenced by both the breathing strength and the interaction strength.Secondly,we calculated the electronic kinetic energy,the direct current conductivity,and the electronic density of states at the Fermi level to determine the critical interaction strength for the metal-insulator transition.Our results indicate that the breathing effect,in conjunction with the interaction strength,drives the kagome system from a metal to an insulator.Finally,we evaluated the magnetic properties and constructed a phase diagram incorporating both transport and magnetic properties.The phase diagram reveals that as the interaction strength increases,the system transitions from a paramagnetic metal to a Mott insulator.Our research provides theoretical guidance for utilizing the breathing effect to control the band gaps,conductivity,and magnetic properties of kagome materials with electronic interactions.展开更多
基金supported by the National Science Foundation of China(Grant No.12474218)Beijing Natural Science Foundation(Grant Nos.1242022 and 1252022).
文摘Inspired by the recent discovery of breathing kagome materials Nb_(3)Cl_(8) and Nb_(3)TeCl_(7),we have explored the influence of the breathing effect on the Hubbard model of the kagome lattice.Utilizing the determinant quantum Monte Carlo method,we first investigated the average sign problem in the breathing kagome lattice,which is influenced by both the breathing strength and the interaction strength.Secondly,we calculated the electronic kinetic energy,the direct current conductivity,and the electronic density of states at the Fermi level to determine the critical interaction strength for the metal-insulator transition.Our results indicate that the breathing effect,in conjunction with the interaction strength,drives the kagome system from a metal to an insulator.Finally,we evaluated the magnetic properties and constructed a phase diagram incorporating both transport and magnetic properties.The phase diagram reveals that as the interaction strength increases,the system transitions from a paramagnetic metal to a Mott insulator.Our research provides theoretical guidance for utilizing the breathing effect to control the band gaps,conductivity,and magnetic properties of kagome materials with electronic interactions.
