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Non-Gaussian fluctuations of mesoscopic persistent currents.
1Dahlem Center for Complex Quantum Systems, Freie Universität Berlin, Berlin, Germany.
Physical Review Letters
|January 15, 2011
Summary
Researchers calculated the leading non-Gaussian correction to persistent current fluctuations in normal-metal rings. This third-order correction, though small, reveals crucial insights into the transition towards Anderson localization.
Area of Science:
- Condensed matter physics
- Quantum transport phenomena
Background:
- Persistent currents in normal-metal rings exhibit sample-to-sample fluctuations.
- These fluctuations are generally Gaussian but show non-Gaussian corrections near the Anderson localization transition.
Purpose of the Study:
- To calculate the leading non-Gaussian correction to the current autocorrelation function.
- To investigate the implications of this correction for understanding Anderson localization.
Main Methods:
- Theoretical calculation of the third-order current autocorrelation function.
- Analysis of the dependence on dimensionless conductance (g).
Main Results:
- The leading non-Gaussian correction to the current autocorrelation function is of third-order.
- This third-order correction is inversely proportional to the dimensionless conductance (g).
- The non-zero nature of this odd moment of the current distribution is a significant finding.
Conclusions:
- The calculated third-order correction provides a precursor signature for the Anderson localization regime.
- Understanding these non-Gaussian corrections is vital for characterizing electron transport in disordered systems.
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