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Effective mass of elementary excitations in Galilean-invariant integrable models

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 Added by Michael Pustilnik
 Publication date 2016
  fields Physics
and research's language is English




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We study low-energy excitations of one-dimensional Galilean-invariant models integrable by Bethe ansatz and characterized by nonsingular two-particle scattering phase shifts. We prove that the curvature of the excitation spectra is described by the recently proposed phenomenological expression for the effective mass. Our results apply to such models as the repulsive Lieb-Liniger model and the hyperbolic Calogero-Sutherland model.



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