Controlling chemistry at extreme time scales

The Nobel Prize in Physics awarded in 2023 underscored the transformative potential of attosecond light sources¹, which now grant us unprecedented insights into the electron time scale within matter. This advancement has paved the way for the emergence of attochemistry^2,3, a novel field aiming at manipulating chemical reactivity through the precise driving of electronic motion.

In this presentation, I will start by explaining the process of attosecond pulse generation^4,5, followed by an overview of our latest achievements in producing few-femtosecond and attosecond light pulses across both ultraviolet (UV)^6,7,8 and soft X-ray spectral ranges⁹. Additionally, I will highlight a variety of applications for these ultrashort light transients, such as the real-time observation of ultrafast charge migration and dissociative dynamics in photoexcited molecules^10,11. A key focus will be on our novel approach to instigating well-controlled charge migration in chiral neutral molecules, which represents a significant step toward achieving charge-directed reactivity¹²—the ultimate objective of attochemistry.

1. F. Calegari et al, J. Phys. B: Atom. Mol. Opt. Phys. 49, 062001 (2016)
2. M. Nisoli, P. Decleva, F. Calegari et al, Chem. Rev. 117, 10760 (2017)
3. F. Calegari, F. Martin, Commun Chem 6, 184 (2023)
4. G. Sansone, E Benedetti, F Calegari, et al, Science 314 (5798), 443-446 (2006)
5. F. Ferrari, F. Calegari et al, Nature Photonics 4 (12), 875-879 (2010)
6. W. Wanie et int, and F. Calegari, J. Phys. Photonics 6, 025005 (2024)
7. V. Wanie et int., and F. Calegari, Rev. Sci. Instrum. 95, 083004 (2024)
8. L. Silletti et int., and F. Calegari, APL Photonics 10, 070801 (2025)
9. A. Azzolin et int, and F. Calegari, J. Phys. Photonics 8, 015057 (2026)
10. F. Calegari et al, Science 346, 336 (2014)
11. L. Colaizzi et int, and F. Calegari, Nature Communications 15 (1), 9196 (2024)
12. V. Wanie et int., and F. Calegari, Nature 630, 109–115 (2024)