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Electron transfer in a two-level system within a Cole-Davidson vitreous bath
Mehdi Zarea1, Mark A Ratner1, Michael R Wasielewski1
1Argonne-Northwestern Solar Energy Research (ANSER) Center, Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, USA.
The Journal of Chemical Physics
|January 21, 2014
Summary
This study compares electron transfer in quantum systems using a viscous Cole-Davidson bath versus a Drude-Debye bath. The viscous bath better preserves quantum coherence at low temperatures but enhances tunneling rates under strong coupling.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Chemical physics
Background:
- Electron transfer (ET) is fundamental in chemical and physical processes.
- Quantum systems coupled to baths exhibit complex dynamics.
- Glassy viscous environments present unique challenges for modeling ET.
Purpose of the Study:
- To investigate electron transfer dynamics in a two-level quantum system.
- To model the bath using the Cole-Davidson (CD) spectral density.
- To compare ET in a CD bath with a conventional Drude-Debye (DD) model.
Main Methods:
- Quantum system coupled to a glassy viscous bath.
- Bath modeled using the Cole-Davidson (CD) spectral density.
- Comparison with the Drude-Debye (DD) model for electron transfer.
Main Results:
- At low temperatures and weak coupling, the CD bath preserves quantum coherence longer than the DD model.
- In the strong coupling regime, the CD model shows a higher tunneling rate.
- At high temperatures (classical limit), differences between CD and DD models become negligible.
Conclusions:
- The choice of bath spectral density significantly impacts electron transfer dynamics.
- Cole-Davidson baths offer advantages in preserving quantum coherence under specific conditions.
- Understanding bath effects is crucial for controlling quantum phenomena in complex systems.
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