Physical Review B
Bethe-ansatz study of the low-temperature thermodynamics of an open Heisenberg chain
Andrei A. Zvyagin, A. V. Makarova
Abstract
Low-temperature thermodynamic characteristics of an antiferromagnetic Heisenberg chain with open boundary conditions are studied with the help of thermodynamic Bethe ansatz. The magnetic susceptibility and low-temperature Sommerfeld coefficient of the specific heat of free edges of the chain diverge with the decrease of temperature, in drastic contrast with the behavior of bulk spins and of the spins in periodic chain.