# Combined visible and near-infrared OPA for wavelength scaling experiments in strong-field physics

## TL;DR

This paper introduces a versatile optical parametric amplifier capable of generating high-power, tunable femtosecond pulses in visible and near-infrared wavelengths, enabling advanced studies of strong-field physics phenomena.

## Contribution

The paper presents a novel OPA with dual operation modes producing high-energy, tunable femtosecond pulses across a broad wavelength range for strong-field experiments.

## Key findings

- Recorded high-order harmonic spectra across various wavelengths
- Demonstrated the OPA's capability for wavelength-dependent strong-field studies
- Provided a flexible tool for exploring multi-photon and tunnel ionization regimes

## Abstract

We report the operation of an optical parametric amplifier (OPA) capable of producing gigawatt peak-power laser pulses with tunable wavelength in either the visible or near-infrared spectrum. The OPA has two distinct operation modes (i) generation of >350 uJ, sub 100 fs pulses, tunable between 1250 - 1550 nm; (ii) generation of >190 uJ, sub 150 fs pulses tunable between 490 - 530 nm. We have recorded high-order harmonic spectra over a wide range of driving wavelengths. This flexible source of femtosecond pulses presents a useful tool for exploring the wavelength-dependence of strong-field phenomena, in both the multi-photon and tunnel ionization regimes.