Measurements of Optical Kerr Nonlinearity n2 in Compressed Gases

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Geints, Yury E., Kompanets, Victor O., Chekalin, Sergey V.
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916910885502976
author Geints, Yury E.
Kompanets, Victor O.
Chekalin, Sergey V.
author_facet Geints, Yury E.
Kompanets, Victor O.
Chekalin, Sergey V.
contents High-power optical pulses experience self-focusing when propagating in a gaseous medium due to the manifestation of the cubic (Kerr-like) nonlinearity. The magnitude of this effect depends on the Kerr nonlinearity coefficient n2, which in turn may depend on the parameters of laser radiation and the propagation medium. We present experimental data on the coefficient n2 for atomic Ar, molecular N2 and CO2 with a pressure change from 1 to 11 bar and optical pulse duration from 50 to 500 fs of propagating femtosecond near-IR laser radiation (800 nm). Importantly, all three gases under study possess close n2-values in the short pulse limit (50 fs) over the entire pressure range. According to our data, for the first time, as far as we know, the Kerr nonlinearity in CO2 is obtained at atmospheric pressure equal to n2(CO2) = 10.0x1.1x10-24 m2/W. Meanwhile, with increasing gas pressure, effective n2 also increases due to the manifestation of aberrational pulse self-focusing caused by the development of modulation instability. In addition, according to our approximate estimate, the magnitude of the inertial component in the cubic nonlinearity of molecular gases (N2, CO2) is substantial and increases with both pulse duration and gas pressure.
format Preprint
id arxiv_https___arxiv_org_abs_2508_15191
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Measurements of Optical Kerr Nonlinearity n2 in Compressed Gases
Geints, Yury E.
Kompanets, Victor O.
Chekalin, Sergey V.
Optics
High-power optical pulses experience self-focusing when propagating in a gaseous medium due to the manifestation of the cubic (Kerr-like) nonlinearity. The magnitude of this effect depends on the Kerr nonlinearity coefficient n2, which in turn may depend on the parameters of laser radiation and the propagation medium. We present experimental data on the coefficient n2 for atomic Ar, molecular N2 and CO2 with a pressure change from 1 to 11 bar and optical pulse duration from 50 to 500 fs of propagating femtosecond near-IR laser radiation (800 nm). Importantly, all three gases under study possess close n2-values in the short pulse limit (50 fs) over the entire pressure range. According to our data, for the first time, as far as we know, the Kerr nonlinearity in CO2 is obtained at atmospheric pressure equal to n2(CO2) = 10.0x1.1x10-24 m2/W. Meanwhile, with increasing gas pressure, effective n2 also increases due to the manifestation of aberrational pulse self-focusing caused by the development of modulation instability. In addition, according to our approximate estimate, the magnitude of the inertial component in the cubic nonlinearity of molecular gases (N2, CO2) is substantial and increases with both pulse duration and gas pressure.
title Measurements of Optical Kerr Nonlinearity n2 in Compressed Gases
topic Optics
url https://arxiv.org/abs/2508.15191