Nonequilibrium photocarrier and phonon dynamics from first principles: a unified treatment of carrier-carrier, carrier-phonon, and phonon-phonon scattering
- 1Department of Physics, University of Trento, Trento, Italy
Abstract
We develop a first-principles many-body framework to describe photocarrier and phonon dynamics in semiconductors after ultrafast excitation. The method includes explicit ab initio light-matter coupling, collision integrals for carrier-carrier, carrier-phonon, and phonon-phonon scattering, time-dependent quasiparticle and phonon-frequency renormalizations, and light-induced coherent atomic motion. The equations of motion are solved in a maximally localized Wannier basis, ensuring gauge-consistent scattering integrals and allowing for dense momentum sampling, enabling direct comparison with pump-probe experiments. The framework is computationally efficient, scalable, and can be combined with constrained density-functional theory to study longer-time light-induced structural phase transitions. We demonstrate the method for MoS 2 and h-BN monolayers. In MoS 2 , it captures photoinduced renormalizations of electronic and lattice properties, ultrafast carrier relaxation, hot-phonon dynamics, and coherent atomic motion. Including carrier-carrier scattering is essential for realistic photocarrier equilibration, while neglecting phonon-phonon scattering yields incorrect long-time lattice thermalization and overestimates the A 1 g coherent-phonon damping time by a factor of two. In h-BN, we quantify photoinduced changes in the electronic, optical, and lattice responses in quasi-equilibrium, demonstrating a fluence-dependent enhancement of screening and melting of excitonic features.
Related
- Electric Field Effects on Amine Regeneration in Post-Combustion Carbon Capture—Part II: Mode-Selective Infrared Laser Excitation Probed by Nonequilibrium Ehrenfest Electron-Nuclear Dynamics
- EXAFS probing of nonequilibrium solvation dynamics of nascent halogen radicals
- A General Non-Markovian Electronic Friction and Langevin Dynamics Framework for Nonequilibrium Systems
- Anisotropic exciton diffusion in O-IDTBR from first-principles molecular dynamics in the first excited state
- S‐Scheme Charge Separation Enables Photocarrier‐Regulated Aqueous NH4 + Storage in g‐C3N4@WO3 Heterojunctions
BibTeX
@article{mocatti2026nonequilibrium,
title = {{Nonequilibrium photocarrier and phonon dynamics from first principles: a unified treatment of carrier-carrier, carrier-phonon, and phonon-phonon scattering}},
author = {Stefano Mocatti and Giovanni Marini and Giulio Volpato and Pierluigi Cudazzo and Matteo Calandra},
journal = {npj Computational Materials},
year = {2026},
month = may,
doi = {10.1038/s41524-026-02104-y},
url = {https://doi.org/10.1038/s41524-026-02104-y},
note = {CC BY},
}
RIS
TY - JOUR
TI - Nonequilibrium photocarrier and phonon dynamics from first principles: a unified treatment of carrier-carrier, carrier-phonon, and phonon-phonon scattering
AU - Stefano Mocatti
AU - Giovanni Marini
AU - Giulio Volpato
AU - Pierluigi Cudazzo
AU - Matteo Calandra
PY - 2026
DA - 2026/05/17
JO - npj Computational Materials
DO - 10.1038/s41524-026-02104-y
UR - https://doi.org/10.1038/s41524-026-02104-y
AB - We develop a first-principles many-body framework to describe photocarrier and phonon dynamics in semiconductors after ultrafast excitation. The method includes explicit ab initio light-matter coupling, collision integrals for carrier-carrier, carrier-phonon, and phonon-phonon scattering, time-dependent quasiparticle and phonon-frequency renormalizations, and light-induced coherent atomic motion. The equations of motion are solved in a maximally localized Wannier basis, ensuring gauge-consistent scattering integrals and allowing for dense momentum sampling, enabling direct comparison with pump-probe experiments. The framework is computationally efficient, scalable, and can be combined with constrained density-functional theory to study longer-time light-induced structural phase transitions. We demonstrate the method for MoS 2 and h-BN monolayers. In MoS 2 , it captures photoinduced renormalizations of electronic and lattice properties, ultrafast carrier relaxation, hot-phonon dynamics, and coherent atomic motion. Including carrier-carrier scattering is essential for realistic photocarrier equilibration, while neglecting phonon-phonon scattering yields incorrect long-time lattice thermalization and overestimates the A 1 g coherent-phonon damping time by a factor of two. In h-BN, we quantify photoinduced changes in the electronic, optical, and lattice responses in quasi-equilibrium, demonstrating a fluence-dependent enhancement of screening and melting of excitonic features.
SN - 2057-3960
ER -