Metamagnetism occurs when the magnetic susceptibility increases with increasing magnetic field. This generally does not occur in weakly interacting systems. For example, if the susceptibility is enhanced by magnetic fluctuations, these are generally decreased by a magnetic field. However, DMFT calculations show this can occur for intermediate coupling. This is discussed in detail in the following paper:
Quasiparticle properties of strongly correlated electron systems with itinerant metamagnetic behavior by J. Bauer
In a Fermi liquid picture the susceptibility can either increase due to an increase in the effective mass or increase due to the quasi-particle interaction F0a (the Landau Fermi liquid parameter which determines the Sommerfeld-Wilson ratio).
Possibly the most promising candidate material for some of this physics is CeRu2Si2. The susceptibility increasses by a factor of more than 8, whereas the specific heat coefficient gamma only increases by a factor of 1.6.
Other candidate heavy fermion materials include YbT2Zn20 (T : Co, Rh, Ir) which is the same family described in an earlier post because it has particularly interesting thermopower.
Subscribe to:
Post Comments (Atom)
Elastic frustration in molecular crystals
Crystals of large molecules exhibit diverse structures. In other words, the geometric arrangements of the molecules relative to one another ...
-
Is it something to do with breakdown of the Born-Oppenheimer approximation? In molecular spectroscopy you occasionally hear this term thro... -
Nitrogen fluoride (NF) seems like a very simple molecule and you would think it would very well understood, particularly as it is small enou... -
Attempts to develop a quantum theory of gravity continue to falter and stagnate. Given this, it is worth considering approaches that start w...
No comments:
Post a Comment