Anomalous thermodynamics of the doped Mott-Hubbard insulators

The concentration dependence of the entropy of doped Mott-Hubbard insulators has been considered within the t - J model. It has been shown that a change in the type and statistics of charge carriers as compared to the Fermi gas leads to a radical change in the entropy s , in particular, to the giant growth of the entropy upon doping. The quantity ∂s/∂x ≈ k B is approximately consistent with the experimental data for HTSC cuprates in the pseudogap phase.