122 citations · 360 across the 24 of their papers we have counts for
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Quantum magnetic phase transitions in a Kugel-Khomskii model including spin-orbit coupling
D. E. Chizhov, P. A. Igoshev, V. Yu. Irkhin
Using the formalism of pseudospin and isospin operators the Hamiltonian of an effective Kugel-Khomskii model with spin-orbit coupling is derived with an exact account of the $t_{2g…
Itinerant electron metamagnetism for lattices with van Hove density-of-states singularities near the Fermi level
F. A. Vasilevskiy, P. A. Igoshev, V. Yu. Irkhin
Itinerant-electron metamagnetism is investigated within the Hubbard model for various lattices having van Hove singularities (vHS) in the electronic spectrum: face-centered cubic a…
Spin-orbit coupling induced orbital entanglement in a three-band Hubbard model
Petr A. Igoshev, Danil E. Chizhov, Valentin Yu. Irkhin +1
The effect of the spin-orbit coupling on the ground state properties of the square-lattice three-band Hubbard model with a single electron per site is studied by a generalized Hart…
Inverse magnetocaloric effect and phase separation induced by giant van Hove singularity in itinerant ferromagnetic metal
Petr A. Igoshev, Igor A. Nekrasov
A thermodynamic theory based on Landau grand potential expansion for ferromagnetic-paramagnetic phase transitions is developed for an electronic phase-separated state. It is rigoro…
Ferromagnetic instability in itinerant fcc lattice electron systems with higher order van Hove singularities: Functional renormalization group study
P. A. Igoshev, A. A. Katanin
We investigate the possibility of ferromagnetic ordering in the non-degenerate Hubbard model on the face-centered cubic lattice within the functional renormalization group techniqu…
Giant density-of-states van Hove singularities in the face-centered cubic lattice
P. A. Igoshev, V. Yu. Irkhin
All van Hove singularities in the density of states (DOS) of face-centered cubic lattice in the nearest and next-nearest neighbour approximation, focusing on higher-order ones, are…
Electron Spectrum Topology and Giant Density-of-States Singularities in Cubic Lattices
P. A. Igoshev, V. Yu. Irkhin
The topology of isoenergetic surfaces in reciprocal space for simple (sc), body-centered (bcc), and face-centered (fcc) cubic lattices is investigated in detail in the tight-bindin…
Emerging mechanisms of magnetocaloric effect in phase-separated metals
V. V. Ivchenko, P. A. Igoshev
We present a study of the magnetocaloric effect in metallic systems exhibiting first-order magnetic transitions and focus on consequences of magnetic phase separation. We account f…
Incommensurate magnetic order in rare earth and transition metal compounds with local moments
A. K. Pankratova, P. A. Igoshev, V. Yu. Irkhin
Within the framework of the - exchange model in the mean-field approximation for square, simple cubic, body-centered and face-centered cubic lattices, the formation of a f…
Metal-insulator transition and antiferromagnetism in the generalized Hubbard model: Treatment of correlation effects
P. A. Igoshev, V. Yu. Irkhin
The ground state for the half-filled Hubbard model is treated within the Hartree-Fock approximation and the slave boson approach including correlations. The criterium for th…
Electron states and magnetic phase diagrams of strongly correlated systems
V. Yu. Irkhin, P. A. Igoshev
Various auxiliary-particle approaches to treat electron correlations in many-electron models are analyzed. Applications to copper-oxide layered systems are discussed. The ground-st…
Magnetic phase transitions and unusual antiferromagnetic states in the Hubbard model
M. A. Timirgazin, P. A. Igoshev, A. K. Arzhnikov +1
Ground state magnetic phase diagrams of the square and simple cubic lattices are investigated for the narrow band Hubbard model within the slave-boson approach by Kotliar and Rucke…
Kohn anomalies in momentum dependence of magnetic susceptibility of some three-dimensional systems
A. A. Stepanenko, D. O. Volkova, P. A. Igoshev +1
We study a question of presence of Kohn points, yielding at low temperatures non-analytic momentum dependence of magnetic susceptibility near its maximum, in electronic spectum of…
Spiral magnetic order, non-uniform states and electron correlations in the conducting transition metal systems
P. A. Igoshev, M. A. Timirgazin, A. K. Arzhnikov +2
The ground-state magnetic phase diagram is calculated within the Hubbard and - exchange (Kondo) models for square and simple cubic lattices vs. band filling and interaction p…
Metal-Insulator Transition in the Hubbard Model: Correlations and Spiral Magnetic Structures
M. A. Timirgazin, P. A. Igoshev, A. K. Arzhnikov +1
The metal--insulator transition (MIT) for the square, simple cubic, and body-centered cubic lattices is investigated within the Hubbard model at half-filling by using both t…
Magnetic States, Correlation Effects and Metal-Insulator Transition in FCC Lattice
M. A. Timirgazin, P. A. Igoshev, A. K. Arzhnikov +1
The ground-state magnetic phase diagram (including collinear and spiral states) of the single-band Hubbard model for the face-centered cubic lattice and related metal-insulator tra…
Magnetic exchange in -iron from the ab initio calculations in the paramagnetic phase
P. A. Igoshev, A. V. Efremov, A. A. Katanin
Applying the local density approximation (LDA) and dynamical mean field theory (DMFT) to paramagnetic -iron, we revisit a problem of theoretical description of its magnetic prop…
Correlation Effects and Non-Collinear Magnetism in the Doped Hubbard Model
P. A. Igoshev, M. A. Timirgazin, V. F. Gilmutdinov +2
The ground--state magnetic phase diagram is investigated for the two-- and three--dimensional -- Hubbard model. We take into account commensurate ferro--, antiferromagnetic,…
Magnetic fluctuations and effective magnetic moments in γ-iron due to electronic structure peculiarities
P. A. Igoshev, A. V. Efremov, A. I. Poteryaev +2
Applying the local density and dynamical mean field approximations to paramagnetic γ-iron we revisit the problem of theoretical description of magnetic properties in a wide tempera…
Ferromagnetism, spiral magnetic structures and phase separation in the two-dimensional Hubbard model
P. A. Igoshev, A. V. Zarubin, A. A. Katanin +1
The quasistatic approximation and equation-of-motion decoupling for the electron Green's functions are applied to trace the effect of electronic dispersion and electron correlation…
Magnetic fluctuations and self--energy effects in two--dimensional itinerant systems with van Hove singularity of electronic spectrum
P. A. Igoshev, V. Yu. Irkhin, A. A. Katanin
We investigate a competition of tendencies towards ferromagnetic and incommensurate order in two-dimensional fermionic systems within functional renormalization group technique usi…
Incommensurate magnetic order and phase separation in the two-dimensional Hubbard model with nearest and next-nearest neighbor hopping
P. A. Igoshev, M. A. Timirgazin, A. A. Katanin +2
We consider the ground state magnetic phase diagram of the two-dimensional Hubbard model with nearest and next-nearest neighbor hopping in terms of electronic density and interacti…
Spin fluctuations and ferromagnetic order in two-dimensional itinerant systems with Van Hove singularities
P. A. Igoshev, A. A. Katanin, H. Yamase +1
The quasistatic approach is used to analyze the criterion of ferromagnetism for two-dimensional (2D) systems with the Fermi level near Van Hove (VH) singularities of the electron s…