Weakly frustrated spin-1/2 Heisenberg antiferromagnet in two dimensions : thermodynamic parameters and the stability of the Néel state

Using a Schwinger-boson mean-field theory, we calculate the low-temperature uniform transverse susceptibility {chi}{sub {perpendicular}} and spin-wave velocity {ital c} for the weakly frustrated spin-1/2 square-lattice Heisenberg antiferromagnet with exchange couplings {ital J}{sub 1}, {ital J}{sub...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B, Condensed matter Condensed matter, 1992-06, Vol.45 (22), p.13121-13124
Main Authors: EINARSSON, T, FRÖJDH, P, JOHANNESSON, H
Format: Article
Language:English
Subjects:
665411 - Basic Superconductivity Studies- (1992-)
ANTIFERROMAGNETISM
BOSON-EXCHANGE MODELS
CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
Condensed matter: electronic structure, electrical, magnetic, and optical properties
CRYSTAL MODELS
Exact sciences and technology
General theory and models of magnetic ordering
HEISENBERG MODEL
HIGH-TC SUPERCONDUCTORS
MAGNETIC PROPERTIES
Magnetic properties and materials
MAGNETIC SUSCEPTIBILITY
MAGNETISM
MATHEMATICAL MODELS
MEAN-FIELD THEORY
PARTICLE MODELS
PERIPHERAL MODELS
PHYSICAL PROPERTIES
Physics
Quantized spin models
SIGMA MODEL
SPIN WAVES
SUPERCONDUCTORS
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Using a Schwinger-boson mean-field theory, we calculate the low-temperature uniform transverse susceptibility {chi}{sub {perpendicular}} and spin-wave velocity {ital c} for the weakly frustrated spin-1/2 square-lattice Heisenberg antiferromagnet with exchange couplings {ital J}{sub 1}, {ital J}{sub 2}, and {ital J}{sub 3} to first, second, and third neighbors. By connecting {chi}{sub {perpendicular}} and {ital c} to the bare coupling of the nonlinear {sigma} model that describes the long-wavelength limit of the antiferromagnet, we are able to improve upon earlier renormalization-group estimates of the zero-temperature phase boundary separating Neel and magnetically disordered ground states. To one-loop level in an {epsilon} expansion we find a disordering transition across a line joining the points ({ital J}{sub 2},{ital J}{sub 3})/{ital J}{sub 1}=(0.15,0) and (0,0.09). Thus, the classical phase boundary ({ital J}{sub 2}+2{ital J}{sub 3})/{ital J}{sub 1}=1/2 is shifted asymmetrically by quantum fluctuations, as expected when the transition is to a columnar dimerized ground state.
ISSN:0163-1829
1095-3795
DOI:10.1103/PhysRevB.45.13121