Electron-Hole Correlation in Fractional Quantum Hall Systems
  The 2D system of electron confined to the lowest Landau level is described using a representation of the density matrix depending both on electron and hole coordinates. Condensation of the electron system into a fractional quantum Hall state is associated to clustering of particle and hole coordinates. The correlation of particle and hole coordinates is studied and groundstate wave functions are derived for $\nu=p/(2p \pm 1)$. These wave functions prove to be accurate for the studied cases $\nu=2/3$ and $3/5$ and are identical to pair wave functions [R. Morf et al., Phys. Rev. B34, 3037 (1986)] for $\nu=2/3$ and $2/5$. 
P. Beran (University Neuchatel, Switzerland)