Sm. Jaya et W. Nolting, QUASI-PARTICLE SPECTRUM OF AN ANTIFERROMAGNETIC LOCAL MOMENT METAL, Physica status solidi. b, Basic research, 208(2), 1998, pp. 497-516
The s-f model is used to describe the temperature dependent electronic
quasiparticle spectrum of a partially filled energy band which is exc
hange coupled to an antiferromagnetically ordered local moment system.
The self-energy of the band electrons is approximately calculated by
the extension of a moment conserving decoupling procedure recently dev
eloped for the description of the ferromagnetic counterpart. Results a
re presented in terms of sublattice quasiparticle band structures, spe
ctral densities. quasiparticle densities of states and characteristic
interband (''mixed s-f'') correlations as functions of temperature T a
nd band occupation n. The temperature dependence of the sublattice ban
d structure is almost exclusively due to a redistribution of spectral
weight between the various quasiparticle branches while their position
s;Ire rather unaffected. As for the ferromagnet, the quasiparticle spl
ittings can be addressed to the formation of a magnetic polaron (propa
gating electron dressed by a virtual cloud of magnons) and to the appe
arance of scattering states (magnon emission and absorption).