Work

Nonlinear refractive index measurements of solids and the impact of B-integral on the phase of generated high-order harmonics

Year: 2025

Type: article

Abstract: We present an interferometric method that employs a birefringent common-path interferometer to measure absolute nonlinear refractive indices in 5 mm thick CaF₂, SiO₂, NBK-7 and KBr for femtosecond pulses at 804-nm center wavelength. The measured nonlinear refractive indices are found to be in agreement with previous literature, over a broad range of pulse energies. In addition, we show and highlight the importance of thorough B-integral characterization when using this birefringent common-path interferometer for high-harmonic generation driven extreme-ultraviolet interferometry. The accumulated third-order nonlinear phase is shown to have significant impact on the harmonic phase after up-conversion to higher orders, but can be accounted for if correctly characterized.

Source: Optics Express

DOI: 10.1364/oe.579736

Authors: Roy van der Linden, Nataliia Kuzkova, Peter M. Kraus

Institution: Vrije Universiteit Amsterdam

Language: English

Topic: Laser-Matter Interactions and Applications

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,270

Funders: Nederlandse Organisatie voor Wetenschappelijk Onderzoek, HORIZON EUROPE European Research Council