Surface hopping dynamics in periodic solid-state materials with a linear vibronic coupling model.

Area of Science:

• Computational materials science
• Quantum chemistry
• Solid-state physics

Background:

• Understanding hot carrier dynamics is crucial for optimizing optoelectronic devices.
• Existing methods often struggle to accurately model relaxation processes in periodic materials.
• Linear vibronic coupling models are essential for describing electron-phonon interactions.

Purpose of the Study:

• To develop and validate an efficient surface hopping approach for simulating hot carrier relaxation dynamics.
• To investigate the influence of reciprocal space sampling on relaxation times.
• To identify the key phonon modes involved in hot carrier relaxation.

Main Methods:

• A surface hopping approach using a linear vibronic coupling Hamiltonian.
• Calculation of model parameters via density-functional theory and perturbation theory.
• Propagation of electronic wavefunctions in reciprocal space with maximally localized Wannier functions.
• Extrapolation of relaxation times using stretched-compressed exponential functions.

Main Results:

• The completeness of Hilbert space k points and phonon q points significantly impacts hot carrier relaxation.
• Accurate hot electron and hole relaxation times were obtained by extrapolating simulation data.
• Long-wave longitudinal optical phonons were identified as dominant in hot carrier relaxation.

Conclusions:

• The developed surface hopping approach provides an efficient and accurate method for modeling photophysical processes in periodic solids.
• Reciprocal space sampling is critical for reliable simulations of hot carrier dynamics.
• Specific phonon modes play a decisive role in energy dissipation mechanisms.