Reduced-Order Modeling Approach for Electron Transport in Molecular Junctions

Area of Science:

• Quantum mechanics
• Condensed matter physics
• Computational physics

Background:

• Describing nonequilibrium transport in quantum devices with infinite baths is computationally challenging.
• Traditional methods often struggle with the complexity of infinite bath interactions.

Purpose of the Study:

• To develop a reduced-order modeling technique for nonequilibrium transport in quantum systems.
• To provide a computationally efficient method for analyzing quantum device behavior.

Main Methods:

• Formulating the problem as a reduced-order problem starting from the Liouville-von Neumann equation.
• Employing the Petrov-Galerkin projection for systematic subspace selection.
• Naturally deriving the self-energy associated with the bath.

Main Results:

• The reduced-order technique yields a finite system with open boundary conditions.
• Numerical experiments confirm the ability of reduced models to capture transient and steady states.
• The self-energy term emerges naturally within the reduced model framework.

Conclusions:

• The proposed reduced-order technique offers an effective approach for studying nonequilibrium transport in quantum devices.
• This method provides accurate predictions for both dynamic and equilibrium behaviors.
• The systematic approach allows for efficient and reliable modeling of complex quantum systems.