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Updated: Jun 2, 2026
11:33
All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Gate-controlled current and inelastic electron tunneling spectrum of benzene: a self-consistent study
Y Y Liang1, H Chen, H Mizuseki
1Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan. liangyy@imr.edu
The Journal of Chemical Physics
|April 19, 2011
Summary
We simulated electron transport through a molecular junction. Gate fields can control current in elastic tunneling, while molecular vibrations affect inelastic electron tunneling.
Area of Science:
- Quantum transport in molecular junctions
- Computational condensed matter physics
Background:
- Understanding electron transport through single molecules is crucial for molecular electronics.
- 1,4-benzenedithiol (BDT) is a common linker molecule in molecular junctions.
Purpose of the Study:
- To investigate the elastic and inelastic electron tunneling properties of a gold-1,4-benzenedithiol-gold molecular junction.
- To explore the effect of an external gate field on current modulation.
- To analyze electron scattering by molecular vibrations.
Main Methods:
- Density functional theory (DFT) based nonequilibrium Green's function (NEGF) formalism.
- Self-consistent calculations for elastic tunneling.
- Self-consistent Born approximation for inelastic electron tunneling.
Main Results:
- Elastic tunneling current is effectively modulated by an external gate field perpendicular to the phenyl ring.
- Gate voltage amplification arises from modulated electrode-molecule interactions.
- Inelastic electron tunneling spectrum was calculated, considering electron scattering by molecular vibrations.
Conclusions:
- Gate field control of current in molecular junctions is feasible.
- Molecular vibrations play a significant role in inelastic electron transport.
- The study provides insights into the fundamental mechanisms governing electron transport in molecular systems.
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