Antiferromagnetic and spiral phases in a [ital t][ital t][prime][ital J] model
Abstract
We present a study of a [ital t][ital t][prime][ital J] model on a square lattice, where [ital t][prime] denotes hopping along the diagonal, within a suitable 1/[ital N] expansion. The [ital T]=0 phase diagram consists of conventional ferromagnetic and incommensurate ([ital Q],[ital Q]) and ([ital Q],0) spiral phases, in addition to an unconventional antiferromagnetic (AF) phase characterized by the usual ([pi],[pi]), i.e., Neel modulation of the spin configuration and an unusual ([pi],[minus][pi]) phase modulation. We obtain the spectrum of elementary excitations for all these phases and explicitly display the associated Goldstonemode structure. A detailed analysis of the AF phase including leading quantumfluctuation effects shows that it remains locally stable at small finite doping, in agreement with the observed behavior in doped antiferromagnets, as well as globally stable against phase separation for sufficiently large [ital t][prime]. A characteristic feature of this AF phase is an [ital anisotropy] in the velocities of its elementary excitations which is suppressed, however, at halffilling. Finally, the spinspin dynamical structure factor in the AF phase is found to exhibit a double peak at finite doping, which reflects hybridization between the relevant transverse (magnonlike) and longitudinal (holonlike) modes, one of the peaks also being suppressed at halffilling.
 Authors:

 Department of Physics, University of Crete, and Research Center of Crete, Heraklion, GR71110 (Greece)
 Publication Date:
 OSTI Identifier:
 5579000
 Resource Type:
 Journal Article
 Journal Name:
 Physical Review, B: Condensed Matter; (United States)
 Additional Journal Information:
 Journal Volume: 48:1; Journal ID: ISSN 01631829
 Country of Publication:
 United States
 Language:
 English
 Subject:
 36 MATERIALS SCIENCE; HEISENBERG MODEL; ANTIFERROMAGNETISM; HOLE MOBILITY; HIGHTC SUPERCONDUCTORS; CUPRATES; HUBBARD MODEL; MAGNONS; TEMPERATURE ZERO K; COPPER COMPOUNDS; CRYSTAL MODELS; MAGNETISM; MATHEMATICAL MODELS; MOBILITY; OXYGEN COMPOUNDS; QUASI PARTICLES; SUPERCONDUCTORS; TRANSITION ELEMENT COMPOUNDS; 360207*  Ceramics, Cermets, & Refractories Superconducting Properties (1992)
Citation Formats
Psaltakis, G C, and Papanicolaou, N. Antiferromagnetic and spiral phases in a [ital t][ital t][prime][ital J] model. United States: N. p., 1993.
Web. doi:10.1103/PhysRevB.48.456.
Psaltakis, G C, & Papanicolaou, N. Antiferromagnetic and spiral phases in a [ital t][ital t][prime][ital J] model. United States. doi:10.1103/PhysRevB.48.456.
Psaltakis, G C, and Papanicolaou, N. Thu .
"Antiferromagnetic and spiral phases in a [ital t][ital t][prime][ital J] model". United States. doi:10.1103/PhysRevB.48.456.
@article{osti_5579000,
title = {Antiferromagnetic and spiral phases in a [ital t][ital t][prime][ital J] model},
author = {Psaltakis, G C and Papanicolaou, N},
abstractNote = {We present a study of a [ital t][ital t][prime][ital J] model on a square lattice, where [ital t][prime] denotes hopping along the diagonal, within a suitable 1/[ital N] expansion. The [ital T]=0 phase diagram consists of conventional ferromagnetic and incommensurate ([ital Q],[ital Q]) and ([ital Q],0) spiral phases, in addition to an unconventional antiferromagnetic (AF) phase characterized by the usual ([pi],[pi]), i.e., Neel modulation of the spin configuration and an unusual ([pi],[minus][pi]) phase modulation. We obtain the spectrum of elementary excitations for all these phases and explicitly display the associated Goldstonemode structure. A detailed analysis of the AF phase including leading quantumfluctuation effects shows that it remains locally stable at small finite doping, in agreement with the observed behavior in doped antiferromagnets, as well as globally stable against phase separation for sufficiently large [ital t][prime]. A characteristic feature of this AF phase is an [ital anisotropy] in the velocities of its elementary excitations which is suppressed, however, at halffilling. Finally, the spinspin dynamical structure factor in the AF phase is found to exhibit a double peak at finite doping, which reflects hybridization between the relevant transverse (magnonlike) and longitudinal (holonlike) modes, one of the peaks also being suppressed at halffilling.},
doi = {10.1103/PhysRevB.48.456},
journal = {Physical Review, B: Condensed Matter; (United States)},
issn = {01631829},
number = ,
volume = 48:1,
place = {United States},
year = {1993},
month = {7}
}