Ultrafast RIXS of orbital-resolved valence-band reshaping in photoexcited graphite.

Authors

Marco Malvestuto, Antonio Caretta, Simone Laterza, Richa Bhardwaj, Beatrice Volpato, Elena Babici, Carlo Alberto Brondin, Michele Manfredda, Alberto Simoncig, Marco Zangrando, Alexander Demidovich, Peter Susnjar, Enrico Massimiliano Allaria, Alexander Darius Brynes, David Garzella, Luca Giannessi, Primož Rebernik Ribič, Filippo Sottocorona, Matteo Zamolo, Alessandro Hervat, Alessandro Gessini, Fulvio Parmigiani, Dino Novko, Elias Richter, Benedikt Maurer, Claudia Draxl

Published in

Science advances. Volume 12. Issue 37. Pages eaeg6983. Sep 11, 2026. Epub Sep 11, 2026.

Abstract

Ultrafast photoexcitation can drive solids far from equilibrium by dynamically renormalizing their electronic structure, yet direct time-domain access to bulk band-structure reshaping with orbital and momentum selectivity has remained limited. Here, we show in photoexcited graphite that femtosecond carbon K-edge resonant inelastic x-ray scattering (RIXS), used in the time domain, provides a momentum- and orbital-selective spectroscopic fingerprint of transient valence-band reshaping. Momentum- and orbital-selective measurements along the [Formula: see text] contour disentangle [Formula: see text] and [Formula: see text] contributions and reveal a structured redistribution of spectral weight emerging within ∼70 femtoseconds and evolving on picosecond timescales. Nonequilibrium first-principles RIXS calculations performed within a frozen-lattice approximation show that the earliest response is dominated by electronic correlations and transient screening. At longer delays, the dynamics become strongly momentum dependent: Near [Formula: see text], the signal reflects the decay of the electronic contribution to the renormalized band structure under a hot-phonon bottleneck, whereas at the [Formula: see text]-point van Hove singularity, it reveals a characteristic spectroscopic signature consistent with electron-phonon-driven band red shift and lifetime broadening induced by strongly coupled optical phonons. A three-temperature model constrained by the orbital-resolved tr-RIXS data captures the ensuing energy cascade through a hot-phonon reservoir dominated by the [Formula: see text] and [Formula: see text] modes. These results establish time-domain RIXS as a complementary probe of transient band-structure renormalization and mode-selective energy flow in quantum materials.

PMID:
42726872
Bibliographic data and abstract were imported from PubMed on 12 Sep 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.