Thermal activation of quasiparticles and thermodynamics of fractional quantum Hall liquids

Quasielectrons and quasiholes in the fractional quantum Hall liquids obey fractional (including nontrivial mutual) exclusion statistics. Their statistics matrix can be determined from several possible state-counting schemes, involving different assumptions on statistical correlations. Thermal activation bf quasiparticle pairs and thermodynamic properties of the fractional quantum Hall liquids near fillings l/m (m odd) at low- temperature are studied in the approximation of generalized ideal gas. The existence of hierarchical states in the fractional quantum Hall effect is shown to be a manifestation of the exclusionary nature of the relevant quasiparticles. For magnetic properties, a paramagnetism-diamagnetism transition appears to be possible at finite temperature. [S0163-1829(98)06616-8].