A tilted pulse-front setup for femtosecond extreme ultraviolet transient grating spectroscopy in highly non-collinear geometries

TL;DR

This paper introduces a tilted pulse-front transient grating technique that enhances time resolution and line density in EUV and SXR transient grating spectroscopy, enabling advanced probing of materials with femtosecond precision.

Contribution

The paper presents a novel optical setup that adapts pulse front tilt for non-collinear geometries, significantly improving temporal resolution in transient grating experiments.

Findings

Achieved 100 fs time resolution, 30 times better than previous setups.

Demonstrated on vanadium dioxide film with 800 nm femtosecond pulses.

Paves the way for EUV and SXR transient grating studies in various materials.

Abstract

We demonstrate a tilted pulse-front transient grating technique that allows to optimally utilize time-resolution as well as transient grating line density while probing under grazing incidence as typically done in extreme ultraviolet (EUV) or soft x-ray (SXR) experiments. Our optical setup adapts the pulse front tilt of the two pulses that create the transient grating to the relative tilt grazing incident pulse. We demonstrate the technique using all 800 nm femtosecond laser pulses for transient grating generation on a vanadium dioxide film. We probe that grating via diffraction of a third 800 nm pulse. The time resolution of 100 fs is an improvement by a factor 30 compared to our previous experiments on the same system (1,2). The scheme paves the way for EUV and SXR probing of optically induced transient gratings on any material.