Molecular recollision interferometry in high harmonic generation.
We use extreme-ultraviolet interferometry to measure the phase of high-order harmonic generation from transiently aligned CO(2) molecules. We unambiguously observe a reversal in phase of the high-order harmonic emission for higher harmonic orders with a sufficient degree of alignment. This results from molecular-scale quantum interferences between the molecular electronic wave function and the recolliding electron as it recombines with the molecule, and is consistent with a two-center model. Furthermore, using the combined harmonic intensity and phase information, we extract accurate information on the dispersion relation of the returning electron wave packet as a function of harmonic order. This analysis shows evidence of the effect of the molecular potential on the recolliding electron wave.
Zhou
Xibin
X
JILA and Department of Physics, University of Colorado and NIST, Boulder, Colorado 80309, USA. Xibin.Zhou@colorado.edu
Lock
Robynne
R
Li
Wen
W
Wagner
Nick
N
Murnane
Margaret M
MM
Kapteyn
Henry C
HC