Time-Linear Quantum Transport Simulations with Correlated Nonequilibrium Green's Functions

Area of Science:

• Quantum physics
• Condensed matter physics
• Computational physics

Background:

• Simulating open and correlated quantum systems out of equilibrium is computationally challenging.
• Real-time characterization of ultrafast quantum phenomena requires efficient theoretical methods.

Purpose of the Study:

• To present a novel time-linear scaling method for simulating open and correlated quantum systems out of equilibrium.
• To enable the real-time characterization of correlated ultrafast phenomena in quantum transport.

Main Methods:

• The method utilizes many-body perturbation theory to selectively include relevant scattering processes.
• Open system dynamics are described using an "embedding correlator" and the Meir-Wingreen formula for time-dependent current.
• The approach is efficiently implemented by integrating with existing time-linear Green's function methods for closed systems.

Main Results:

• The proposed method achieves time-linear scaling for simulating open and correlated quantum systems.
• It allows for the selective inclusion of scattering processes, crucial for understanding complex dynamics.
• Electron-electron and electron-phonon interactions are treated simultaneously while conserving fundamental laws.

Conclusions:

• The developed method provides an efficient and accurate way to simulate non-equilibrium quantum dynamics.
• It opens new avenues for studying ultrafast phenomena in quantum transport and correlated systems.
• The approach preserves fundamental conservation laws, ensuring physical consistency.