Magnetic properties of half metal from the paramagnetic phase: DFT+DMFT study of exchange interactions in CrO${}_2$

Abstract

We study magnetic properties of CrO${}_2$ within the density functional theory plus dynamical mean-field theory (DFT+DMFT) approach in the paramagnetic phase. We consider the 3-orbital (per Cr site) model, containing only $t_{2g}$ states, the $5$-orbital model, including all $d$-states, as well as the model including also the oxygen $p$-states. Using the recently proposed approach of calculation of exchange interactions in paramagnetic phase, we extract exchange interaction parameters and magnon dispersions for these models. While the magnon dispersion in the 3-orbital model possesses negative branches in accordance with previous studies in ferromagnetic phase, this drawback is removed in the $5$-orbital model. The model including oxygen states (with purely local interaction at chromium sites) overestimates the exchange interactions and spin wave stiffness. While this overestimate is partly corrected by including non-local interaction between chromium and oxygen states within mean-field approximation, the $5$-orbital model appears as most adequate for describing magnetic properties of CrO${}_2$ with local Coulomb interaction. The possibility of describing magnetic properties of this material starting from paramagnetic phase points to the correspondence of magnetic properties in this phase and ferromagnetic phase, as well as important contributions of double exchange in paramagnetic phase of CrO${}_2$.

arXiv comment12 pages, 6+2 figures

References in corpus (45)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Wannier90 as a community code: new features and applications
• A continuous-time solver for quantum impurity models
• Half-metallic ferromagnets: From band structure to many-body effects
• Continuous Time Quantum Monte Carlo method for fermions
• CrO2: a self-doped double exchange ferromagnet
• Diagrammatic routes to nonlocal correlations beyond dynamical mean field theory
• Band Structure and Transport Properties of CrO_2
• Spin freezing transition and non-Fermi-liquid self-energy in a 3-orbital model
• Weak Pseudogap Behavior in the Underdoped Cuprate Superconductors
• Microscopic theory of weak pseudogap behavior in the underdoped cuprate superconductors I: General theory and quasiparticle properties
• Local magnetic moments in iron and nickel at ambient and Earth's core conditions
• Electronic correlations at the alpha-gamma structural phase transition in paramagnetic iron
• Calculated phonon spectra of paramagnetic iron at the alpha-gamma phase transition
• Orbital selective local moment formation in iron: first principle route to an effective model
• Half-Metallic Ferromagnetism and the spin polarization in CrO${}_2$
• $i$QIST: An open source continuous-time quantum Monte Carlo impurity solver toolkit
• Electronic correlations determine the phase stability of iron up to the melting temperature
• Self-consistent Dual Boson approach to single-particle and collective excitations in correlated systems
• Orbital character of O 2p unoccupied states near the Fermi level in CrO2
• Importance of d-p Coulomb interaction for high T${}_C$ cuprates and other oxides
• Mechanisms and origins of half-metallic ferromagnetism in CrO2
• Model Hamiltonian parameters for half-metallic ferromagnets NiMnSb and CrO2
• Effective crystal field and Fermi surface topology: a comparison of d- and dp-orbital models
• Quantum Monte Carlo study for multiorbital systems with preserved spin and orbital rotational symmetries
• Anomalous self-energy and Fermi surface quasi-splitting in the vicinity of a ferromagnetic instability
• $i$QIST v0.7: An open source continuous-time quantum Monte Carlo impurity solver toolkit
• Ab initio calculations with the dynamical vertex approximation
• Determining the Anisotropic Exchange Coupling of CrO_2 via First-Principles Density Functional Theory Calculations
• Weakly-correlated nature of ferromagnetism in non symmorphic CrO${}_2$ revealed by bulk-sensitive soft X ray ARPES
• Orbital Correlations in the Ferromagnetic Half-Metal $CrO_{2}
• Momentum-dependent susceptibilities and magnetic exchange in bcc iron from supercell DMFT calculations
• Charge self-consistent electronic structure calculations with dynamical mean-field theory using Quantum ESPRESSO, Wannier90 and TRIQS
• Extracting Kondo temperature of strongly-correlated systems from the inverse local magnetic susceptibility
• Exchange interactions in iron and nickel: DFT+DMFT study in paramagnetic phase
• Electronic self-energy and triplet pairing fluctuations in the vicinity of a ferromagnetic instability in 2D systems: the quasistatic approach
• Fermi surface expansion above critical temperature in a Hund ferromagnet
• DFT+DMFT study of exchange interactions in cobalt and their implications for the competition of hcp and fcc phases
• Linear response theories for interatomic exchange interactions
• Spectral functions of 2D systems with coupling of electrons to collective or localized spin degrees of freedom
• Charge and spin correlations in insulating and incoherent metal states of twisted bilayer graphene
• MXene Fe2C as a promising candidate for the 2D XY ferromagnet
• Generalized dynamical mean-field theory of two-subalttice systems with non-local interactions and its application to study charge and spin correlations in graphene
• Band filling dependence of the Curie temperature in CrO2

Cited by in corpus (4)

• Magnetic properties of monolayer, multilayer, and bulk CrTe${}_2$
• Splitting of electronic spectrum in paramagnetic phase of itinerant ferromagnets and altermagnets
• Exchange interactions in itinerant magnets: the effects of local particle-hole irreducible vertex corrections and SU(2) symmetry of Hund interaction
• Evolution of Correlated Electrons in $\mathrm{L}{\mathrm{a}}_3\mathrm{N}{\mathrm{i}}_2{\mathrm{O}}_7$ at Ambient Pressure: a Study of Double-Counting Effect