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Published on: November 11, 2013
Bound states in time-dependent quantum transport: oscillations and memory effects in current and density
E Khosravi1, G Stefanucci, S Kurth
1Institut für Theoretische Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany.
Physical Chemistry Chemical Physics : PCCP
|May 29, 2009
Summary
Localized current oscillations in nanoscale electronic systems can persist indefinitely, exceeding steady currents. These oscillations and density changes depend on the system's history, offering new ways to define non-equilibrium states.
Area of Science:
- Condensed matter physics
- Quantum electronics
- Nanoscale systems
Background:
- Understanding electron behavior in nanoscale electronic systems is crucial.
- Investigating phenomena at the interface of quantum mechanics and macroscopic electrodes is an active research area.
- Characterizing non-equilibrium states in electronic systems presents theoretical challenges.
Purpose of the Study:
- To investigate the emergence of persistent current oscillations in nanoscale electronic systems.
- To analyze the dependence of these oscillations on the applied potential history.
- To define bound-state occupations out of equilibrium.
Main Methods:
- Theoretical modeling of nanoscale electronic systems connected to biased electrodes.
- Analysis of electron dynamics and charge density under applied potentials.
- Investigation of history-dependent effects on system properties.
Main Results:
- Demonstrated persistent, non-decaying, localized current oscillations.
- Observed that oscillation amplitude depends on the entire history of the applied potential.
- Showed that bound-state contribution to time-averaged density is history-dependent.
Conclusions:
- Bound states in nanoscale systems can drive significant, persistent current oscillations.
- The history of applied potentials fundamentally influences non-equilibrium electronic states.
- A novel definition for out-of-equilibrium bound-state occupations is established.
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