Spectral functions of 2D systems with coupling of electrons to collective or localized spin degrees of freedom

Abstract

The spectral properties of itinerant 2D systems with (nearly) ferromagnetic ground state are studied within the spin-fermion and the classical s-d exchange models. While the former model describes the effect of collective magnetic excitations on the electronic properties, the latter one considers the effect of local moments. We use the equation of motion approach combined with the 1/M and 1/z expansions (M is the number of spin components, z is the coordination number) to investigate spectral functions. In both the models the spectrum splitting occurs at low temperatures T in the renormalized classical regime due to strong magnetic fluctuations. For the interaction J between electronic and magnetic degrees of freedom comparable to the bandwidth (the intermediate-coupling regime) the 1/z expansion predicts full splitting of electronic spectrum below some temperature T_s. At the same time, the spectrum remains only partly split in the 1/M expansion with the quasiparticle structure which becomes fully coherent at low T.

arXiv comment13 pages, 10 figures, RevTex

References in corpus (29)

• Quantum Cluster Theories
• Cellular Dynamical Mean Field Approach to Strongly Correlated Systems
• Nonlocal Dynamical Correlations of Strongly Interacting Electron Systems
• Theory of Two-Dimensional Quantum Heisenberg Antiferromagnets with a Nearly Critical Ground State
• Dynamical vertex approximation - a step beyond dynamical mean field theory
• Antiferromagnetism and d-wave superconductivity in cuprates: a uster DMFT study
• Non-perturbative many-body approach to the Hubbard model and single-particle pseudogap
• Nodal quasiparticle in pseudogapped colossal magnetoresistive manganites
• Weak Pseudogap Behavior in the Underdoped Cuprate Superconductors
• Nonanalytic behavior of the spin susceptibility in clean Fermi systems
• Quantum-critical behavior of itinerant ferromagnets
• Pseudogap in High - Temperature Superconductors
• Microscopic theory of weak pseudogap behavior in the underdoped cuprate superconductors I: General theory and quasiparticle properties
• Non-analytic corrections to the Fermi-liquid behavior
• Fermi surface fluctuations and single electron excitations near Pomeranchuk instability in two dimensions
• Influence of Spatial Correlations in Strongly Correlated Electron Systems: Extension to Dynamical Mean Field Approximation
• Temperature-Dependent Pseudogaps in Colossal Magnetoresistive Oxides
• Antiferromagnetism and single-particle properties in the two-dimensional half-filled Hubbard model: a non-linear sigma model approach
• First order superconducting transition near a ferromagnetic quantum critical point
• Continuous quantum phase transition in a Kondo lattice model
• Models of the Pseudogap State of Two-Dimensional Systems
• Anomalous self-energy and Fermi surface quasi-splitting in the vicinity of a ferromagnetic instability
• Self-generated locality near a ferromagnetic quantum-critical point
• Density-of-states picture and stability of ferromagnetism in the highly-correlated Hubbard model
• Magnetic fluctuations and itinerant ferromagnetism in two-dimensional systems with van Hove singularities
• Electronic self-energy and triplet pairing fluctuations in the vicinity of a ferromagnetic instability in 2D systems: the quasistatic approach
• Metal-insulator transition in the Hubbard model: a simple description including the Kondo effect
• The Kondo effect in periodic narrow-band systems
• Magnetic properties of a Kondo insulator with RKKY interaction: Extended dynamical mean field study

Cited by in corpus (9)

• Modern Physics of the Condensed State: Strong Correlations and Quantum Topology
• Fermi surface expansion above critical temperature in a Hund ferromagnet
• Spin fluctuations and ferromagnetic order in two-dimensional itinerant systems with Van Hove singularities
• The Kondo-lattice state and non-Fermi-liquid behavior in the presence of Van Hove singularities
• Magnetic properties of half metal from the paramagnetic phase: DFT+DMFT study of exchange interactions in CrO${}_2$
• Formation of exotic states in the $s-d$ exchange and $t-J$ models
• A Contemporary Model Description of Magnetism
• A Modern Model Description of Magnetism
• Diagrammatic bosonization, aspects of criticality, and the Hohenberg-Mermin-Wagner theorem in parquet approaches