High-order harmonic spectroscopy for molecular imaging of polyatomic molecules

TL;DR

This paper advances high-order harmonic spectroscopy to enable molecular imaging of complex polyatomic molecules, demonstrating the technique on N2O and C2H2, paving the way for imaging fragile biological compounds.

Contribution

It extends molecular orbital tomography to more complex molecules like N2O and C2H2, overcoming previous limitations for larger, fragile molecules.

Findings

Successful application to N2O and C2H2 molecules

Demonstration of imaging complex polyatomic molecules

Progress towards imaging biological molecules

Abstract

High-order harmonic generation is a powerful and sensitive tool for probing atomic and molecular structures, combining in the same measurement an unprecedented attosecond temporal resolution with a high spatial resolution, of the order of the angstrom. Imaging of the outermost molecular orbital by high-order harmonic generation has been limited for a long time to very simple molecules, like nitrogen. Recently we demonstrated a technique that overcame several of the issues that have prevented the extension of molecular orbital tomography to more complex species, showing that molecular imaging can be applied to a triatomic molecule like carbon dioxide. Here we report on the application of such technique to nitrous oxide (N2O) and acetylene (C2H2). This result represents a first step towards the imaging of fragile compounds, a category which includes most of the fundamental biological molecules.