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  • Elucidating the origin of laser-induced nonlinearities in propagation inside transparent media: a comparative numerical study of silicon and fused silica
Title: Elucidating the origin of laser-induced nonlinearities in propagation inside transparent media: a comparative numerical study of silicon and fused silica
Abstract The creation of localized bulk modification using femtosecond pulses inside semiconductors like silicon (Si) is quite challenging, whereas it is not difficult to achieve it for dielectric materials like fused silica (FS). This report addresses the fundamental origin of this issue. By taking a simple numerical approach, it has been found that in FS we can deliver stronger fluence due to self-focusing at higher power levels compared to Si. The origin for the above lies in the spatio-temporal pulse-splitting behavior, which is dominant in the case of FS at the focus, whereas, for Si, it is only effective after focus. We have also considered the influence of plasma and Kerr terms to elucidate the reason behind these nonlinearities. For the FS case, omission of Kerr term dominates, whereas, for Si, the influence of each term does not significantly create self-focusing like FS under a similar focusing condition. This study could provide an important guideline for researchers to understand the complexity of laser-matter interaction in transparent materials specifically being studied by many laser-processing industries.  more » « less
Award ID(s):
2129006
PAR ID:
10655956
Author(s) / Creator(s):
;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Journal of Physics: Photonics
Volume:
6
Issue:
4
ISSN:
2515-7647
Page Range / eLocation ID:
045016
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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