Magnetic and thermodynamic properties of correlated fermions : application to liquid ^{3}He

We have analyzed the Hubbard model within an extended Gutzwiller approach, which eliminates original statistical inconsistencies. Within this approximation, for both simple and facecentered cubic lattices we have calculated the magnetic field dependence of the spin polarization and have found a good semi-quantitative agreement with experimental data concerning bulk liquid ^{3}He. Within the range of parameters describing the experimental magnetization curve at ambient pressure, our model does not show a pronounced metamagnetic transition predicted within the original Gutzwiller approach. However, the field dependent magnetic susceptibility and the specific heat show hallmarks of the metamagnetic-like behavior.