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arXiv · 2601.16786

Unified First-Principles Formula for Time-Resolved ARPES Spectra of Coherent and Incoherent Excitons

Gianluca Stefanucci·Enrico Perfetto
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Abstract

Despite major experimental progresses in time-resolved and angle-resolved photoemission spectroscopy, a quantitative, microscopic framework for interpreting exciton-induced modifications of electronic band structures -- applicable even beyond the low-density limit -- is still lacking. Here we close this gap by introducing a unified approach that links the dynamics of coherent and incoherent excitons to distinct and experimentally observable excitonic sidebands. Our central result is a general, first-principles formula for time-resolved photoemission spectra, applicable across a broad range of temperatures, excitation densities, and pump-probe delays. This advance provides a predictive tool for quantitatively tracking excitonic dynamics in complex materials.

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Gianluca Stefanucci, Enrico Perfetto. 2026-01-23. Unified First-Principles Formula for Time-Resolved ARPES Spectra of Coherent and Incoherent Excitons. https://arxiv.org/abs/2601.16786

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