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Stability analysis of multiple nonequilibrium fixed points in self-consistent electron transport calculations
1Department of Physics, Université Libre de Bruxelles, Campus Plaine, Brussels, Belgium.
The Journal of Chemical Physics
|November 11, 2011
Summary
We developed a method to analyze the stability of electron transport calculations. This method uses a stability matrix derived from linearized kinetic equations to predict long-term behavior in nonequilibrium systems.
Area of Science:
- Condensed Matter Physics
- Quantum Chemistry
- Computational Materials Science
Background:
- Electron transport calculations are crucial for understanding molecular electronics.
- Nonequilibrium fixed points in these calculations require stability analysis for accurate predictions.
- Existing methods may lack efficiency in assessing the long-term behavior of these systems.
Purpose of the Study:
- To introduce a novel method for stability analysis of nonequilibrium fixed points in self-consistent electron transport calculations.
- To provide a framework for assessing the asymptotic time behavior of these systems.
- To derive stability matrices applicable to common theoretical frameworks.
Main Methods:
- Linearizing the stationary, nonlinear kinetic equation for the single-particle density matrix around fixed points.
- Obtaining the stability matrix by analyzing the real part of its spectrum.
- Deriving expressions for stability matrices within Hartree-Fock (HF) and linear response adiabatic time-dependent density functional theory (TDDFT).
- Applying the nonequilibrium HF approximation for stability analysis of electron transport through a molecule with a spin-degenerate single level and local Coulomb interaction.
Main Results:
- A systematic method for stability analysis of nonequilibrium fixed points has been established.
- The real part of the stability matrix spectrum accurately predicts the asymptotic time behavior.
- Expressions for stability matrices were derived for HF and TDDFT.
- The method was successfully applied to analyze electron transport through a model molecular system.
Conclusions:
- The presented method offers a robust approach to stability analysis in electron transport calculations.
- This technique enhances the reliability of theoretical predictions for molecular electronic devices.
- The derived stability matrices provide valuable tools for computational studies in condensed matter physics and quantum chemistry.
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