Effect of weak disorder in the fully frustrated XY model
INFM Unità di Napoli, Dipartimento di Scienze Fisiche, Mostra D'Oltremare Pad. 19, 80125 Napoli, Italy
Accepted: 29 September 1998
The critical behaviour of the fully frustrated XY model in the presence of weak positional disorder is studied in a square lattice by Monte Carlo methods. The critical exponent associated to the divergence of the chiral correlation length is found to be already at very small values of disorder. Furthermore the helicity modulus jump is found larger than the universal value expected in the XY model.
PACS: 64.60.Cn – Order-disorder transformations; statistical mechanics of model systems / 75.10.Hk – Classical spin models / 75.40.Mg – Numerical simulation studies
© EDP Sciences, 1998