Physical review. B, Condensed matter
Reply to ‘‘Comment on ‘Low-temperature properties of the Hubbard chain with an attractive interaction’ ’’
P. Schlottmann
Abstract
In the preceding Comment, the energy of the system is expanded at a van Hove singularity of one band as a function of changes in the field, the magnetization, and the Fermi energy. Unfortunately, not all the derivatives are properly defined at a van Hove singularity. This leads to the erroneous conclusion that the susceptibility is finite at the critical point. The correct result is that M\ensuremath{\propto}(H-${\mathit{H}}_{\mathit{c}}$${)}^{1/2}$, in analogy to a Prokovsky-Talapov transition.