390 citations · 564 across the 10 of their papers we have counts for
6 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…
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…
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…
Spin-stiffness of anisotropic Heisenberg model on square lattice and possible mechanism for pinning of the electronic liquid crystal direction in YBCO
T. Pardini, R. R. P. Singh, A. Katanin +1
Using series expansions and spin-wave theory we calculate the spin-stiffness anisotropy in Heisenberg models on the square lattice with anisotropic couplings $J_x,J…
Renormalization group for phases with broken discrete symmetry near quantum critical points
P. Jakubczyk, P. Strack, A. A. Katanin +1
We extend the Hertz-Millis theory of quantum phase transitions in itinerant electron systems to phases with broken discrete symmetry. Using a set of coupled flow equations derived…