Related Experiment Video
Updated: Oct 20, 2025

An Experimental Protocol for Femtosecond NIR/UV - XUV Pump-Probe Experiments with Free-Electron Lasers
Published on: October 23, 2018
Enhancement of Above Threshold Ionization in Resonantly Excited Helium Nanodroplets
R Michiels1, M Abu-Samha2, L B Madsen3
1Institute of Physics, University of Freiburg, 79104 Freiburg, Germany.
Abstract:
Clusters and nanodroplets hold the promise of enhancing high-order nonlinear optical effects due to their high local density. However, only moderate enhancement has been demonstrated to date. Here, we report the observation of energetic electrons generated by above-threshold ionization (ATI) of helium (He) nanodroplets which are resonantly excited by ultrashort extreme ultraviolet (XUV) free-electron laser pulses and subsequently ionized by near-infrared (NIR) or near-ultraviolet (UV) pulses. The electron emission due to high-order ATI is enhanced by several orders of magnitude compared with He atoms. The crucial dependence of the ATI intensities with the number of excitations in the droplets suggests a local collective enhancement effect.
More Related Videos
08:22Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
12:57Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Related Concept Videos
Nuclear Overhauser Enhancement (NOE)
π Electron Effects on Chemical Shift: Overview
Chemical Ionization (CI) Mass Spectrometry
Ionization Energy
Electrospray Ionization (ESI) Mass Spectrometry
ESI utilizes electrical energy to transfer ions from the liquid phase of the sample into the...
Molecular Orbital Theory II