447 citations · 3.8k across the 103 of their papers we have counts for
8 papers · 1 filter
Universal properties of frustrated spin systems: 1/N-expansion and renormalization group approaches
A. N. Ignatenko, V. Yu. Irkhin, A. A. Katanin
We consider a quantum two-dimensional O(N)xO(2)/O(N-2)xO(2) nonlinear sigma model for frustrated spin systems and formulate its 1/N-expansion which involves fluctuating scalar and…
Strong short-range magnetic order in a frustrated FCC lattice and its possible role in the iron structural transformation
A. N. Ignatenko, A. A. Katanin, V. Yu. Irkhin
We investigate magnetic properties of a frustrated Heisenberg antiferromagnet with a face-centered cubic (FCC) lattice and exchange interactions between the nearest- and next-neare…
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…
Comparing pertinent effects of antiferromagnetic fluctuations in the two and three dimensional Hubbard model
A. A. Katanin, A. Toschi, K. Held
We use the dynamical vertex approximation (DA) with a Moriyaesque correction for studying the impact of antiferromagnetic fluctuations on the spectral function of the Hubb…
Dynamical vertex approximation -- an introduction
K. Held, A. A. Katanin, A. Toschi
We give an elementary introduction to a recent diagrammatic extension of dynamical mean field theory (DMFT) coined dynamical vertex approximation (DA). This approach contains th…
The two-loop functional renormalization-group approach to the one- and two-dimensional Hubbard model
A. A. Katanin
We consider the application of the two-loop functional renormalization-group (fRG) approach to study the low-dimensional Hubbard model. This approach accounts for both, the univers…