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 $\mu$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.

References in corpus (2)

• High harmonic generation from Bloch electrons in solids
• Imperfect Recollisions in High-Harmonic Generation in Solids

Cited by in corpus (5)

• Observation of light driven band structure via multi-band high harmonic spectroscopy
• Spectral control of high order harmonics through non-linear propagation effects
• Multiband dynamics of extended harmonic generation in solids under ultraviolet injection
• Femtosecond currents in transition metal dichalcogenides monolayers
• Non-linear propagation effects of intense femtosecond pulses on low order harmonics in solids