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arXiv · 2607.17265

First-principles electron-phonon scattering in real-time TDDFT

Zhengwei Nie·Subhojit Pal·Marti Lüders·Alexander Buccheri·Hannes Hübener·Shunsuke A. Sato·Umberto De Giovannini
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Abstract

Real-time time-dependent density functional theory provides a first-principles description of coherent electron dynamics in laser-driven solids, but its unitary formulation cannot capture the irreversible scattering, relaxation, and decoherence processes that drive excited carriers toward equilibrium. Here, we develop a dissipative rt-TDDFT framework in which first-principles electron-phonon interactions enter the evolution of the reduced one-body density matrix through self-energy-derived collision integrals within the Born-Markov approximation. The approach retains the quantum-coherent real-time propagation of the electronic system while introducing phonon-mediated transitions that redistribute carriers in energy and crystal momentum, thereby incorporating the microscopic momentum-transfer processes responsible for relaxation in real materials. The resulting framework provides a practical first-principles route to simulate relaxation, decoherence, and time-resolved spectroscopic signatures in realistic crystalline materials.

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Zhengwei Nie, Subhojit Pal, Marti Lüders, Alexander Buccheri, Hannes Hübener, Shunsuke A. Sato, Umberto De Giovannini. 2026-07-19. First-principles electron-phonon scattering in real-time TDDFT. https://arxiv.org/abs/2607.17265

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