FermiLiquidVerhalten

FermiLiquidVerhalten refers to the characteristic thermodynamic and transport properties of a Fermi liquid, a quantum mechanical model describing the collective behavior of a system of interacting fermions at low temperatures. In a Fermi liquid, the elementary excitations are not the individual fermions themselves, but rather quasiparticles. These quasiparticles carry the same quantum numbers as the original fermions but have modified properties due to interactions.

The Landau theory of Fermi liquids provides a framework for understanding this behavior. Key concepts include the quasiparticle distribution function and Landau parameters, which describe the interactions between quasiparticles. These parameters determine deviations from the properties of a non-interacting Fermi gas. For instance, the effective mass of a quasiparticle can be significantly different from its free-fermion mass, and its magnetic susceptibility can be enhanced.

At low temperatures, the specific heat of a Fermi liquid is linear in temperature, similar to a non-interacting Fermi gas. However, the coefficient of this linear term is modified by the Landau parameters. Transport properties, such as electrical and thermal conductivity, also reflect the quasiparticle picture. Scattering processes between quasiparticles become important, leading to a temperature dependence of resistivity that is typically quadratic at low temperatures. The Fermi liquid model has been highly successful in explaining experimental observations in systems like liquid helium-3 and conduction electrons in metals.