Properties of Heavy Fermion Materials
Heavy fermion materials belong to the group of strongly correlated electron systems.
Several members of the group of heavy fermion materials, become superconducting below a critical temperature. The superconductivity is unconventional.
At high temperatures heavy fermion compounds behave like normal metals and the electrons can be described as a Fermi gas, in which the electrons are assumed to be non-interacting fermions. In this case the interaction between the f-electrons, which present a local magnetic moment and the conduction electrons is neglected.
The Fermi liquid theory by Landau provides a good model to describe the properties of most heavy fermion materials at low temperatures. In this theory the electrons are described by quasiparticles, which have the same quantum numbers and charge, but the interaction of the electrons is taken into account by introducing an effective mass, which differs from the actual mass of a free electron.
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