Equation of state of an anyon gas in a strong magnetic field.

The statistical mechanics of an anyon gas in a magnetic field is addressed. An harmonic regulator is used to define a proper thermodynamic limit. When the magnetic field is sufficiently strong, only exact N -anyon groundstates, where anyons occupy the lowest Landau level, contribute to the equation of state. Particular attention is paid to the interval of definition of the statistical parameter α ∈ [−1, 0] where a gap exists. Interestingly enough, one finds that at the critical filling ν = −1/α where the pressure diverges, the external magnetic field is entirely screened by the flux tubes carried by the anyons. PACS numbers: 05.30.-d, 11.10.-z IPNO/TH 93-16 (APRIL 1993) and LPTPE, Tour 16, Université Paris 6 / electronic e-mail: OUVRY@FRCPN11 Unité de Recherche des Universités Paris 11 et Paris 6 associée au CNRS