Presenting exact solutions for the two-dimensional periodic Anderson model with finite and nonzero on-site interactions U>0, we describe a rigorous non-Fermi-liquid phase in normal phase and two dimensions. This new state emerges in multiband interacting Fermi systems above half filling, being generated by a flat-band effect. The momentum distribution function nk- together with its derivatives of any order is continuous. The state possesses a well-defined Fermi energy (ef), but the Fermi momentum concept is not definable, so the Fermi surface in k space is missing. The state emerges in the vicinity of a Mott insulating phase when lattice distortions are present and is highly degenerated and paramagnetic. A gap is present at high U in the density of low-lying excitations. During low-lying excitations, quasiparticles are not created above the Fermi level, only the number of particles at eF increases.
|Number of pages||4060640|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Jul 15 2001|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics