Manifestation of spin and charge fluctuations in spectral and thermodynamic properties of quasi-two-dimensional rare-earth intermetallics
V.V. Val’kov and A.O. Zlotnikov
L.V. Kirenskiy Institute of Physics, Siberian Branch of the Russian Academy of Sciences Krasnoyarsk 660036, Russia
Received August 1, 2016
In the framework of the modified periodic Anderson model including the exchange interaction in the subsystem of localized states, it is shown that the spin and charge fluctuations in the quasi-two-dimensional intermetallic compounds with rare-earth ions in the mixed valence state significantly affect both the spectrum of magnetic excitations and the conditions of implementation of the antiferromagnetic phase. The spectral characteristics of the phase have been obtained by the method of the diagram technique for Hubbard operators using the one-loop approximation, allowing to take into account the spin-charge fluctuation contributions to the components of the mass and the strength operators. The developed theory allowed to quantitatively describe the Néel temperature dependence on pressure observed in the quasi-two-dimensional antiferromagnetic intermetallic compound with heavy fermions CeRhIn5.
PACS: 71.27.+a Strongly correlated electron systems; heavy fermions; PACS: 75.50.Ee Antiferromagnetics; PACS: 75.30.Et Exchange and superexchange interactions; PACS: 75.40.Gb Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.).
Key words: heavy fermions, antiferromagnetism, spin-charge fluctuations, CeRhIn5, periodic Anderson model.