Dephasing rate formula in the many-body context
Abstract
We suggest a straightforward approach to the calculation of the dephasing rate in a fermionic system, which correctly keeps track of the crucial physics of Pauli blocking. Starting from Fermi’s golden rule, the dephasing rate can be written as an integral over the frequency transferred between system and environment, weighted by their respective spectral densities. We show that treating the full many-fermion system instead of a single particle automatically enforces the Pauli principle. Furthermore, we explain the relation to diagrammatics. Finally, we show how to treat the more involved strong-coupling case when interactions appreciably modify the spectra. This is relevant for the situation in disordered metals, where screening is important.
- Publication:
-
Physical Review B
- Pub Date:
- December 2009
- DOI:
- 10.1103/PhysRevB.80.245410
- arXiv:
- arXiv:0909.1441
- Bibcode:
- 2009PhRvB..80x5410C
- Keywords:
-
- 03.65.Yz;
- 74.40.+k;
- 73.23.-b;
- Decoherence;
- open systems;
- quantum statistical methods;
- Fluctuations;
- Electronic transport in mesoscopic systems;
- Condensed Matter - Mesoscale and Nanoscale Physics;
- Condensed Matter - Strongly Correlated Electrons;
- Quantum Physics
- E-Print:
- 12 pages, 3 figures, some textual improvements, to be published in PRB