Space-averaged non-equilibrium Green's function approach for quantum transport in 3D.

Area of Science:

• Computational Physics
• Quantum Mechanics
• Materials Science

Background:

• Mesoscopic systems and nanoscale electronic devices require advanced simulation methods.
• Existing 2D non-equilibrium Green's function (NEGF) implementations face limitations in three dimensions.
• Effective-mass based 3D NEGF simulations are crucial for next-generation devices.

Purpose of the Study:

• To extend a 2D finite-volume (FV) implementation of NEGF to a full 3D framework.
• To address key implementation challenges associated with 3D NEGF simulations.
• To provide a practical tool for simulating open quantum systems in three dimensions.

Main Methods:

• Development of a 3D finite-volume (FV) discretization for the NEGF approach.
• Comparison with traditional Finite Difference (FD) implementations of NEGF.
• Formulation for evaluating self-energies, incorporating reservoir effects.

Main Results:

• Demonstration of FV discretization's effectiveness in overcoming 3D NEGF implementation challenges.
• Successful evaluation of self-energies within the 3D FV-NEGF framework.
• Illustration of the method's applicability through two distinct examples.

Conclusions:

• The developed 3D FV-NEGF implementation offers a robust solution for simulating mesoscopic systems.
• This method is particularly valuable for open quantum systems requiring a fully three-dimensional domain.
• The work paves the way for more accurate simulations of complex nanoscale electronic devices.