Comment on "Six-state clock model on the square lattice: Fisher zero approach with Wang-Landau sampling"

Seung Ki Baek, Petter Minnhagen, Beom Jun Kim
2010 Physical Review E  
Hwang in [Phys. Rev. E 80, 042103 (2009)] suggested that the two transitions of the six-state clock model on the square lattice are not of the Kosterlitz-Thouless type. Here we show from simulations thatat the upper transition, the helicity modulus does make a discontinuous jump to zero. This gives strong evidence for a Kosterlitz-Thouless transition.
doi:10.1103/physreve.81.063101 pmid:20866464 fatcat:qsqrhvzrqzgknkohwlwzjjmwre