We are excited to share our latest preprint. Utilizing our unique cryogenic attosecond beamline, we identified distinct core-level signatures of CDW formation in time-resolved measurements that were undetectable in equilibrium photoemission and absorption measurements in the putative excitonic insulator TiSe2. We also observe excitonic correlations in the normal-state of the material above the transition temperature. These findings provide crucial insights into the mechanism of exciton condensation in this material, highlighting the interplay between short-range excitonic fluctuations and long-range order. Our work underscores the importance of attosecond spectroscopy in exploring both equilibrium phase diagrams and novel nonequilibrium states in strongly correlated materials.

Preprint available here: https://arxiv.org/abs/2407.00772