1994/09/21 by A. Honecker, Honecker, A.
Mathematics · Physics and Astronomy · #Algebraic structures and combinatorial models #Condensed Matter (cond-mat) #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Theory (hep-th) #Physics of Superconductivity and Magnetism #Quantum many-body systems
paper · pdf · doi:10.48550/arxiv.hep-th/9409122
openalex publication_date 1994/09/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The massive high-temperature phase of the chiral Potts quantum chain is studied using perturbative methods. For the Z3-chain we present high-temperature expansions for the groundstate energy and the dispersion relations of the two single-particle states as well as two-particle states at general values of the parameters. We also present a perturbative argument showing that a large class of massive Zn-spin quantum chains have quasiparticle spectra with n-1 fundamental particles. It is known from earlier investigations that -at special values of the parameters- some of the fundamental particles exist only for limited ranges of the momentum. In these regimes our argument is not rigorous as one can conclude from a discussion of the radius of convergence of the perturbation series. We also derive correlation functions from a perturbative evaluation of the groundstate for the Z3-chain. In addition to an exponential decay we observe an oscillating contribution. The oscillation length seems to be related to the asymmetry of the dispersion relations. We show that this relation is exact at special values of the parameters for general Zn using a form factor expansion.