2003/12/17 by I. Milat, Fakher F. Assaad, F. F. Assaad +2 · 34 citations
Physics and Astronomy · #Condensed matter physics #Hubbard model #Magnetic field #Monte Carlo method #Phase (matter) #Phase diagram #Phase transition #Physics #Physics of Superconductivity and Magnetism #Quantum Monte Carlo #Quantum and electron transport phenomena #Quantum mechanics #Quantum phase transition #Rare-earth and actinide compounds #Superconductivity #cond-mat.str-el
paper · pdf · doi:10.1140/epjb/e2004-00154-5
published in The European Physical Journal B 38(4), 571-580 (Springer Science+Business Media) · 10 pages, 8 figures (revTeX 4), submited to EPJ B
arxiv created 2003/12/17 · openalex publication_date 2004/04/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the 2D Kondo insulators in a uniform magnetic field using quantum Monte Carlo simulations of the particle-hole symmetric Kondo lattice model and a mean field analysis of the Periodic Anderson model. We find that the field induces a transition to an insulating, antiferromagnetically ordered phase with staggered moment in the plane perpendicular to the field. For fields in excess of the quasi-particle gap, corresponding to a metal in a simple band picture of the periodic Anderson model, we find that the metallic phase is unstable towards the spin density wave type ordering for any finite value of the interaction strength. This can be understood as a consequence of the perfect nesting of the particle and hole Fermi surfaces that emerge as the field closes the gap. We propose a phase diagram and investigate the quasi-particle and charge excitations in the magnetic field. We find good agreement between the mean-field and quantum Monte Carlo results.