Physical review. B, Condensed matter
Finite temperature excitations of the quantum sine-Gordon–massive Thirring model: Variation of the soliton mass with coupling constant and temperature
Michael Durnan Johnson, Michael Fowler
Abstract
For the quantum sine-Gordon--massive Thirring model at finite temperature, the relationship between the Bethe ansatz ``elementary excitations'' and physical excitations of the system is examined. The thermodynamic equations are written in terms of a set of dressed particles in the general case. We find that the recently predicted soliton mass discontinuity (on varying coupling strength at finite temperature) is not a real effect--the function exhibiting the discontinuity does not correspond to the mass of the soliton.