Competing effective interactions of Dirac electrons in the Spin-Fermion system
arXiv:2009.14424 · doi:10.1016/j.aop.2013.10.007
Abstract
Recently discovered advanced materials, such as heavy fermions, frequently exhibit a rich phase diagram suggesting the presence of different competing interactions. A unified description of the origin of these multiple interactions, albeit very important for the comprehension of such materials is, in general not available. It would be therefore very useful to have a simple model where the common source of different interactions could be possibly traced back. In this work we consider a system consisting in a set of localized spins on a square lattice with antiferromagnetic nearest neighbors interactions and itinerant electrons, which are assumed to be Dirac-like and interact with the localized spins through a Kondo magnetic interaction. This system is conveniently described by the Spin-Fermion model, which we use in order to determine the effective interactions among the itinerant electrons. By integrating out the localized degrees of freedom we obtain a set of different interactions, which includes: a BCS-like superconducting term, a Nambu-Jona-Lasinio-like, excitonic term and a spin-spin magnetic term. The resulting phase diagram is investigated by evaluation of the mean-field free-energy as a function of the relevant order parameters. This shows the competition of the above interactions, depending on the temperature, chemical potential and coupling constants.
arXiv commentarXiv admin note: substantial text overlap with arXiv:1109.2151
References in corpus (23)
- Correlated Electrons in High Temperature Superconductors
- Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
- Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
- Heavy Fermions and Quantum Phase Transitions
- Theory of Underdoped Cuprates
- Pseudogap state from quantum criticality
- Observation of Dirac Cone Electronic Dispersion in BaFe2As2
- Electron and hole Dirac cone states in-pairs in Ba(FeAs) confirmed by magnetoresistance
- Superconductivity coexisting with phase-separated static magnetic order in (Ba,K)FeAs, (Sr,Na)FeAs and CaFeAs
- Quantum Criticality and Superconductivity in Quasi-Two-Dimensional Dirac Electronic Systems
- Magnetization of Planar Four-Fermion Systems
- Anomalous f-electron Hall Effect in the Heavy-Fermion System CeTIn (T = Co, Ir, or Rh)
- Quantum-critical superconductivity in underdoped cuprates
- Magnetic and superconducting instabilities in a hybrid model of itinerant/localized electrons for iron pnictides
- Strongly Interacting Two-Dimensional Dirac Fermions
- Robust d-wave Pairing Correlations in the Heisenberg Kondo Lattice Model
- Asymmetrically Doped Polyacetylene
- Superconducting and excitonic quantum phase transitions in doped systems with Dirac electrons
- A New Quantum Vortex Operator and Its Correlation Functions
- Charge pairing, superconducting transition and supersymmetry in high-temperature cuprate superconductors
- Magnetic and Quasiparticle Excitation Spectra of an Itinerant Model for Iron Pnictide Superconductors
- Superconductivity in graphene stacks: from the bilayer to graphite
- From the spin-fermion model to anisotropic superconductivity