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Negative Electronic Friction and Non-Markovianity in Nonequilibrium Quantum Systems
R J Preston1, S L Rudge1, D S Kosov2
1Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg, Germany.
Nano Letters
|June 12, 2026
Summary
Negative electronic friction in molecular systems arises from vibrational coupling to electronic transitions, leading to non-Markovian effects. This impacts molecular dynamics and system stability beyond standard heating.
Area of Science:
- Quantum dynamics
- Molecular electronics
- Surface science
Background:
- Nonadiabatic molecular dynamics
- Electronic friction
- Nonequilibrium conditions
Purpose of the Study:
- Investigate the link between negative electronic friction and non-Markovian effects.
- Analyze vibrational dynamics in molecules on metal surfaces.
- Understand charge transport in molecular nanojunctions.
Main Methods:
- Theoretical modeling of molecular nanojunctions.
- Analysis of nonequilibrium charge transport.
- Numerical simulations using hierarchical equations of motion.
Main Results:
- A mechanism for negative electronic friction also generates non-Markovian effects.
- Negative electronic friction drives vibrational modes beyond Joule heating.
- Non-Markovian effects significantly alter nonequilibrium dynamics and Langevin equation stability.
Conclusions:
- Non-Markovian effects are intrinsically linked to negative electronic friction in molecular systems.
- Understanding these effects is crucial for predicting molecular dynamics and stability.
- The findings advance the theory of quantum transport in molecular junctions.
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