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Exact trimer ground states on a spin-1 chain

106   0   0.0 ( 0 )
 Added by J. Solyom
 Publication date 1999
  fields Physics
and research's language is English




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We construct a new spin-1 model on a chain. Its ground state is determined exactly which is three-fold degenerate by breaking translational invariance. Thus we have trimerization. Excited states cannot be obtained exactly, but we determine a few low-lying ones by using trial states, among them solitons.



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