Néel orders, Haldane gap, and Kondo singlet phase in the anisotropic Kondo chain

Naokazu Shibata; Chikara Ishii; Kazuo Ueda

doi:10.1103/PhysRevB.51.3626

Néel orders, Haldane gap, and Kondo singlet phase in the anisotropic Kondo chain

Naokazu Shibata, Chikara Ishii, and Kazuo Ueda

Phys. Rev. B 51, 3626 – Published 1 February 1995

Abstract

The ground-state phase diagram of the Kondo chain with an anisotropic exchange is investigated. Four different phases are identified, two types of Néel phases, the Haldane phase, and the Kondo singlet phase. The boundaries between these phases in the strong coupling region are determined by mapping to effective models: the spin-1 Heisenberg model with single-ion anisotropy and the Ising model in a transverse magnetic field. It is shown that these transition lines extend to the weak-coupling limit and they are estimated by using the exact numerical diagonalization for a finite system.

Received 28 October 1994

DOI:https://doi.org/10.1103/PhysRevB.51.3626

Authors & Affiliations

Naokazu Shibata

Department of Physics, Faculty of Science, Science University of Tokyo, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162, Japan
Institute for Solid State Physics, University of Tokyo, 7-22-1 Roppongi, Minato-ku Tokyo 106, Japan

Chikara Ishii