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arXiv:cond-mat/0606813 · Physical Review B

Variational coupled-cluster study of plasmonlike excitations in quantum antiferromagnets

Yang Xian

Published Dec 8, 2006• 8 citations
arXivHTMLPDF

Abstract

We study plasmonlike excitations in quantum antiferromagnets by the recently proposed variational coupled-cluster method. Within our approximation, we find that these spin-zero excitations have a nonzero energy gap in a cubic lattice and are gapless in a square lattice, similar to the plasmons in quantum electron gases.
DOI
10.1103/physrevb.74.212401

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