Physical review. B, Condensed matter
New renormalization equations for the Kosterlitz-Thouless transition
Petter Minnhagen
Abstract
A new set of renormalization equations for the two-dimensional Coulomb gas is derived and solved numerically. These equations give a new picture of the Kosterlitz-Thouless transition. A new temperature ${T}^{\mathrm{*}}$ is found. Above ${T}^{\mathrm{*}}$ the value of the dielectric constant at the transition is ${\ensuremath{\epsilon}}_{c}$=1/(4${T}_{c}$) as before whereas below ${T}^{\mathrm{*}}$ the new result ${\ensuremath{\epsilon}}_{c}$1/(4${T}_{c}$) is obtained. The singular behavior at ${T}^{\mathrm{*}}$ is explored. The results are translated into a renormalization-group flow diagram. An interesting consequence is that the universal jump prediction for the Kosterlitz-Thouless transition turns into a nonuniversal jump prediction for critical temperatures below ${T}^{\mathrm{*}}$.