Decoherence of Fermions Subject to a Quantum Bath
The destruction of quantum-mechanical phase coherence by a fluctuating quantum bath has been investigated mostly for a single particle. However, for electronic transport through disordered samples and mesoscopic interference setups, we have to treat a many-fermion system subject to a quantum bath. Here, we review a novel technique for treating this situation in the case of ballistic interferometers, and discuss its application to the electronic Mach-Zehnder setup. We use the results to bring out the main features of decoherence in a many-fermion system and briefly discuss the same ideas in the context of weak localization.
KeywordsShot Noise Weak Localization Zehnder Interferometer Pauli Blocking Classical Noise
Unable to display preview. Download preview PDF.
- E. Joos et al.: Decoherence and the Appearance of a Classical World in Quantum Theory (Springer, Heidelberg, 2003)Google Scholar
- K. Blum, Density Matrix Theory and Applications (Plenum, New York, 1996)Google Scholar
- U. Weiss: Quantum Dissipative Systems (World Scientific, Singapore, 2000)Google Scholar
- Y. Imry: Introduction to Mesoscopic Physics, 2nd ed. (Oxford University Press, 2002)Google Scholar
- S. Pilgram, P. Samuelsson, H. Förster, M. Büttiker: Full counting statistics for voltage and dephasing probes, cond-mat/0512276Google Scholar
- F. Marquardt: Equations of motion approach to decoherence and current noise in ballistic interferometers coupled to a quantum bath, cond-mat/0604458 (2006)Google Scholar
- F. Marquardt, J. v. Delft, R. Smith, V. Ambegaokar: Decoherence in weak localization I: Pauli principle in influence functional, cond-mat/0510556Google Scholar
- J. v. Delft, F. Marquardt, R. Smith, V. Ambegaokar: Decoherence in weak localization II: Bethe-Salpeter calculation of Cooperon, cond-mat/0510557; J. v. Delft: Influence functional for decoherence of interacting electrons in disordered conductors, cond-mat/0510563Google Scholar
- In contrast, the decoherence rate given in Ref.  is equal to that obtained for a single particle, with f = 0 in our formula, thus saturating at T = 0. We should note that the authors of Ref.  disagree with our conclusions, see their comment: D. S. Golubev and A. D. Zaikin, cond-mat/0512411.Google Scholar