Universal behavior of heavy-fermion metals near a quantum critical point
V. R. Shaginyan
Petersburg Nuclear Physics Institute, 188300 Gatchina, Russia
CTSPS, Clark Atlanta University, 30314 Atlanta, Georgia, USA
PACS: 71.10.Hf, 71.27.+a, 75.30.Cr
Abstract
The behavior of the electronic system of heavy fermion metals
is considered. We show that there exist at least two main types of the
behavior when the system is nearby a quantum critical point which can be
identified as the fermion condensation quantum phase transition
(FCQPT). We show that the first type is represented by the behavior of
a highly correlated Fermi-liquid, while the second type is depicted
by the behavior of a strongly correlated Fermi-liquid.
If the system approaches FCQPT from the disordered phase,
it can be viewed as a highly correlated Fermi-liquid which at low
temperatures exhibits the behavior of Landau Fermi liquid (LFL).
At higher temperatures T, it demonstrates the non-Fermi liquid (NFL)
behavior which can be converted into the LFL behavior by the application
of magnetic fields B. If the system has undergone FCQPT,
it can be considered as a strongly
correlated Fermi-liquid which demonstrates the NFL behavior even at
low temperatures. It can be turned into LFL by applying magnetic
fields B. We show that the effective mass M* diverges at the
very point that the Neél temperature goes to zero. The B-T phase
diagrams of both liquids are studied. We demonstrate that these
B-T phase diagrams have a strong impact on the main properties of
heavy-fermion metals such as the magnetoresistance, resistivity,
specific heat, magnetization, volume thermal expansion, etc.