Attosecond synchronization of extreme ultraviolet high harmonics from crystals
Abstract
The interaction of strong near-infrared (NIR) laser pulses with wide-bandgap dielectrics produces high harmonics in the extreme ultraviolet (XUV) wavelength range. These observations have opened up the possibility of attosecond metrology in solids, which would benefit from a precise measurement of the emission times of individual harmonics with respect to the NIR laser field. Here we show that, when high-harmonics are detected from the input surface of a magnesium oxide crystal, a bichromatic probing of the XUV emission shows a clear synchronization largely consistent with a semiclassical model of electron-hole recollisions in bulk solids. On the other hand, the bichromatic spectrogram of harmonics originating from the exit surface of the 200 m-thick crystal is strongly modified, indicating the influence of laser field distortions during propagation. Our tracking of sub-cycle electron and hole re-collisions at XUV energies is relevant to the development of solid-state sources of attosecond pulses.
Keywords
Cite
@article{arxiv.2001.09951,
title = {Attosecond synchronization of extreme ultraviolet high harmonics from crystals},
author = {Giulio Vampa and Jian Lu and Yong Sing You and Denitsa R. Baykusheva and Mengxi Wu and Hanzhe Liu and Kenneth J. Schafer and Mette B. Gaarde and David A. Reis and Shambhu Ghimire},
journal= {arXiv preprint arXiv:2001.09951},
year = {2020}
}