Time-resolved study of resonant interatomic Coulombic decay in helium nanodroplets
Abstract
When weakly-bound complexes are multiply excited by intense electromagnetic radiation, energy can be exchanged between neighboring atoms through a type of resonant interatomic Coulombic decay (ICD). This decay mechanism due to multiple excitations has been predicted to be relatively slow, typically lasting tens to hundreds of picoseconds. Here, we directly measure the ICD timescale in resonantly excited helium droplets using a high resolution, tunable, extreme ultraviolet free electron laser. Over an extensive range of droplet sizes and laser intensities, we discover the decay to be surprisingly fast, with decay times as fast as 400 femtoseconds, and to only present a weak dependence on the density of the excited states. Using a combination of time dependent density functional theory and ab initio quantum chemistry calculations, we elucidate the mechanisms of this ultrafast decay process where pairs of excited helium atoms in one droplet strongly attract each other and form merging void bubbles which drastically accelerates ICD.
Keywords
Cite
@article{arxiv.2009.01758,
title = {Time-resolved study of resonant interatomic Coulombic decay in helium nanodroplets},
author = {A. C. LaForge and R. Michiels and Y. Ovcharenko and A. Ngai and J. M. Escartin and N. Berrah and C. Callegari and A. Clark and M. Coreno and R. Cucini and M. Di Fraia and M. Drabbels and E. Fasshauer and P. Finetti and L. Giannessi and C. Grazioli and D. Iablonskyi and B. Langbehn and T. Nishiyama and V. Oliver and P. Piseri and O. Plekan and K. C. Prince and D. Rupp and S. Stranges and K. Ueda and N. Sisourat and J. Eloranta and M. Pi and M. Barranco and F. Stienkemeier and T. Moeller and M. Mudrich},
journal= {arXiv preprint arXiv:2009.01758},
year = {2021}
}