Low temperature phase diagram and critical behaviour of the four-state chiral clock model
M. Pleimling, B. Neubert and R. Siems
The low temperature behaviour of the four-state chiral clock ($CC_4$) model is reexamined
using a systematic low temperature series expansion of the free energy.
Previously obtained results for the low temperature phases
are corrected and the low temperature phase diagram is
In addition, the phase transition from the modulated region to the high temperature paraphase
is shown to belong to the universality class of the 3d-$XY$ model.