 Heavy fermion material

A strongly correlated material whose low-energy electronic quasiparticles have a very large thermodynamic effective mass. An enhanced electronic heat capacity coefficient, spin susceptibility and quantum-oscillation cyclotron effective mass are complementary signatures; they need not all be related by a single isotropic band mass. A Kondo lattice is an important setting for such behaviour. In CeAl3, low-temperature specific heat and quadratic resistivity provided an early quantitative example.^[ref]