# Green's Functions in Nonequilibrium

## Lecture details

The lecture will be given by Professor Schoeller.

**Prerequisites:**

- elementary knowledge about many-body theory of quantum systems, see e.g. the lecture on "Quantum theory of condensed matter I" given in the first Master semester
- 2. quantization, field operators, Wick theorem, definition and properties of Greens- and correlation functions in equilibrium, Matsubara formalism, linear response theory, electrons, phonons, random impurities
- suitable for students in the third Master semester

**
Description:
**

This lecture contains an introduction to nonequilibrium Greens functions (Keldysh formalism):

- Introduction to real time Greens functions
- diagrammatic expansion, Feynman diagrams, path integral formalism
- derivation of Dyson equation
- derivation of quantum Boltzmann equations: gradient expansion, quasiparticle approximation, quasiclassical approximation
- application to random impurities, electron-phonon interaction, electron-electron interaction
- Fermi liquid theory
- derivation of linearized quantum Boltzmann equations, calculation of conductivity
- application to mesoscopic systems

**Related Lecture:**

Parallel to this lecture there is a lecture on Open quantum systems, where n onequilibrium properties of small quantum systems coupled to a dissipative environment are discussed based on the Liouville operator formalism.

**
Subsequent Lecture:
**

In the next summer semester there will be a continuation of this lecture by Dr. Severin Jakobs combining Keldysh formalism with functional renormalization group methods and applying the formalism to one- and zero-dimensional electronic systems coupled to reservoirs.

For more details please refer to the university calendar.

Time | Room | Starts |
---|---|---|

Tues. 10am - 12.30pm | 4263 (26 C 401) | 20.10.2014 (14 dates) |