Prof. RNDr. Václav Janiš, DrSc.

Office: C440b, UTIA-Building



Phone: +420 26605 2153


Email: janis@fzu.cz

Vita

Research

Publications (PDF)

Research interests:

Theory of strongly correlated electrons
Model description of electron correlations, Hubbard and Anderson impurity models, collective and cooperative phenomena, transition from weak to strong coupling regimes, breakdown of Fermi-liquid phase, (dynamical) mean-field theory for intermediate and strong coupling, Kondo and insulating regimes; implementation of electron correlations in realistic calculational schemes

Quantum coherence and quantum phase transitions in itinerant systems
Quantitative description of quantum criticality, interaction-driven quantum phase transitions in metals, effects of noncommutativity of relevant operators on critical behavior, formation of bound and resonant pair states, structure of order parameters of quantum phases, transverse magnetic order, superconductivity

Transport properties of disordered electron systems
Vertex corrections in the electrical conductivity in impure metals, quantum diffusion and coherence, diagrammatic theory of weak and strong electron localization, metal-insulator transition

Theory of spin glasses and other random systems
Mean-field theory based on real replicas in the thermodynamic approach of Thouless, Anderson and Palmer for Ising and Heisenberg spin glasses and related models

Field-theoretic and diagrammatic methods for quantum two-particle functions
Feynman diagrams and many-body Green functions for nonrelativistic quantum interacting systems, advanced approximations for two-particle Green functions, vertex corrections, parquet approach to two-particle vertex functions

Nonequilibrium phenomena
Quantum nonequilibrium systems, nonequilibrium Green functions and transport equations, x-ray edge problem and orthogonality catastrophe, two-level systems in a phonon bath

University courses:

Thermodynamics and Statistical Physics I (course in Czech)

Thermodynamics and Statistical Physics II (course in Czech)

Statistical physics of quantum many-particle systems I

Statistical physics of quantum many-particle systems II

Renormalization theory of phase transitions

Study opportunities

Diploma theses

PhD theses

Research opportunities

Postdoc positions

Selected recent publications

V. Pokorný and V. Janiš,Vertex corrections to the mean-field electrical conductivity in disordered electron systems, J. Phys.: Condens. Matter 25 175502 (2013) 1-10.

V. Janiš, A. Kauch, and A. Klíč, Free energy of mean-field spin-glass models: Evolution operator and perturbation expansion, Phys. Rev. B 87, 054201 (2013) 1-11

V. Janiš and A. Kllíč, Mean-field solution of the Potts glass near the transition temperature to the ordered phase, Phys. Rev. B 84, 064446 (2011) 1-10.

V. Janiš and V. Pokorný, Renormalized perturbation theories of Anderson localization: Self-consistent two-particle vertices, Ann. Phys. (Berlin) 523 (2011) 715-23.

P. Augustinský and V. Janiš, Multiorbital simplified parquet equations for strongly correlated electrons, Phys. Rev. B 83, 035114 (2011)1 - 13.

V. Janiš and V. Pokorný, Vertex corrections to the electrical conductivity in models with elastically scattered electrons, Phys. Rev. B 81, 165103 (2010) 1-9.

V. Janiš, Free-energy functional for the Sherrington-Kirkpatrick model: The Parisi formula completed, Phys. Rev. B 77,104417 (2008) 1 - 5.