Spiral magnetic phases on the Kondo Lattice Model: A Hartree–Fock approach
Autor: | Raimundo R. dos Santos, Natanael C. Costa, José P. de Lima |
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Rok vydání: | 2017 |
Předmět: |
Physics
Strongly Correlated Electrons (cond-mat.str-el) Condensed matter physics Magnetism Kondo insulator FOS: Physical sciences 02 engineering and technology 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Square lattice Electronic Optical and Magnetic Materials Condensed Matter - Strongly Correlated Electrons 0103 physical sciences Antiferromagnetism Condensed Matter::Strongly Correlated Electrons Kondo effect 010306 general physics 0210 nano-technology Ground state Lattice model (physics) Phase diagram |
Zdroj: | Journal of Magnetism and Magnetic Materials. 423:74-83 |
ISSN: | 0304-8853 |
Popis: | We study the Kondo Lattice Model (KLM) on a square lattice through a Hartree-Fock approximation in which the local spins are treated semi-classically, in the sense that their average values are modulated by a magnetic wavevector $\mathbf{Q}$ while they couple with the conduction electrons through fermion operators. In this way, we obtain a ground state phase diagram in which spiral magnetic phases (in which the wavevector depends on the coupling constants and on the density) interpolate between the low-density ferromagnetic phase and the antiferromagnetic phase at half filling; within small regions of the phase diagram commensurate magnetic phases can coexist with Kondo screening. We have also obtained `Doniach-like' diagrams, showing the effect of temperature on the ground state phases, and established that for some ranges of the model parameters (the exchange coupling and conduction electron density) the magnetic wavevector changes with temperature, either continuously or abruptly (e.g., from spiral to ferromagnetic). 13 pages, 15 figures |
Databáze: | OpenAIRE |
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