MAGNETIC PHASE DIAGRAM OF THE HUBBARD MODEL ON THE AB₂ CHAIN

Abstract

In this paper, a complete investigation of the magnetic properties of the Hubbard model on the AB 2 chain is presented. We evaluate the magnetic phase diagram as a function of the electron-electron interaction and band filling by using the Green's function method within the Hartree-Fock approximation. Our results are in agreement with Lieb's theorem and the system shows ferromagnetic, ferrimagnetic, and paramagnetic phases.