Coherent diffractive imaging of single helium nanodroplets with a high harmonic generation source

TL;DR

This paper demonstrates the first single-shot coherent diffractive imaging of helium nanodroplets using a lab-based high harmonic generation source, enabling detailed structural analysis without large-scale facilities.

Contribution

It introduces a novel method for single-shot imaging of nanoparticles with lab-based XUV pulses, expanding the accessibility of ultrafast nanoscopy.

Findings

Successful imaging of helium nanodroplets with bright scattering patterns

Identification of previously unresolved prolate shapes of helium droplets

Paves the way for ultrafast imaging with phase-controlled multicolor and attosecond pulses

Abstract

Coherent diffractive imaging of individual free nanoparticles has opened novel routes for the in-situ analysis of their transient structural, optical, and electronic properties. So far, single-shot single-particle diffraction was assumed to be feasible only at extreme ultraviolet (XUV) and X-ray free-electron lasers, restricting this research field to large-scale facilities. Here we demonstrate single-shot imaging of isolated helium nanodroplets using XUV pulses from a femtosecond-laser driven high harmonic source. We obtain bright wide-angle scattering patterns, that allow us to uniquely identify hitherto unresolved prolate shapes of superfluid helium droplets. Our results mark the advent of single-shot gas-phase nanoscopy with lab-based short-wavelength pulses and pave the way to ultrafast coherent diffractive imaging with phase-controlled multicolor fields and attosecond pulses.