# Towards attosecond pulse synthesis from solids: spectral shaping, field autocorrelation, and two-color harmonic generation

## TL;DR

This paper demonstrates spectral shaping and coherence control of high harmonics generated from solids, advancing the development of attosecond pulse sources for ultrafast science.

## Contribution

It introduces methods for spectral shaping and coherence measurement of solid-state harmonic generation, enabling attosecond pulse synthesis from solids.

## Key findings

- Spectral shaping achieves bandwidth suitable for attosecond pulses.
- Harmonic field autocorrelation shows attosecond spikes.
- High spatial coherence of the harmonic beam is confirmed.

## Abstract

Harmonic generation from solid surfaces is a promising tool for producing high energy attosecond pulses. We report shaping of the harmonic spectrum to achieve the bandwidth necessary for attosecond pulse generation. The shaping is demonstrated for lower as well as for higher harmonics using single and two-pulse pumping. The measured harmonic field autocorrelation function exhibits attosecond spikes in good agreement with the harmonic spectrum. Double slit experiments reveal a high spatial coherence of the harmonic beam.