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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Current-induced light emission and light-induced current in molecular-tunneling junctions
Michael Galperin1, Abraham Nitzan
1School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel.
Physical Review Letters
|December 31, 2005
Summary
This study reveals light-induced current in metal-molecule-metal junctions with strong charge-transfer transitions. It also shows current-induced light emission, suggesting observable optoelectronic effects in molecular junctions.
Area of Science:
- Molecular electronics
- Optoelectronics
- Condensed matter physics
Background:
- Metal-molecule-metal junctions are crucial for molecular electronics.
- Understanding light-matter interactions in these nanoscale systems is key.
Purpose of the Study:
- To model light-induced current and current-induced light emission in molecular junctions.
- To investigate the role of molecular charge-transfer transitions and excitation energy.
Main Methods:
- Development of a simple generic model for metal-molecule-metal junctions.
- Analysis of light-matter and electron-molecule interactions within the model.
Main Results:
- Demonstration of light-induced current in unbiased junctions with strong charge-transfer transitions.
- Prediction of current-induced light emission when bias exceeds molecular excitation energy.
Conclusions:
- The proposed model highlights new optoelectronic functionalities in molecular junctions.
- Both light-induced current and current-induced light emission are predicted to be experimentally observable.
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