J. Phys. I France 2 (1992) 371-377
Self-consistent interaction of magnons in a frustrated quantum antiferromagnetL. Bergomi and Th. Jolicoeur
Service de Physique Théorique, C.E. Saclay, F-91191 Gif-sur-Yvette Cedex, France
(Received 19 December 1991, accepted 27 January 1992)
We study the magnon interactions by means of a self-consistent calculation in a frustrated quantum Heisenberg antiferromagnet with first and second neighbor exchange couplings. We have used the Hartree-Fock-Bogolyubov scheme at zero temperature. The effect of frustration on the shape of the spin-wave spectrum is investigated: we find a strong decrease of the spin-wave velocity. A clear deviation from spin wave theory is found when comparing with finite lattice results.
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