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Title: Wavelength scaling of the high-intensity laser pulse compression dynamics in gas-filled capillaries
The multimodal carrier-resolved unidirectional pulse propagation equation is solved to study the wavelength-dependent (λ = 1, 2, 3 and 4 μm) spatio-temporal dynamics, particularly pulse self-compression during high-intensity laser pulse propagation in gas-filled capillaries. We find that pulse self-compression in gas-filled capillaries due to plasma is more efficient for short wavelengths in contrast to wavelength-dependent pulse self-compression in laser filamentation [1]. To explain our finding, a detailed analysis is performed by quantifying the contributions of higher-order modes and calculating the temporal delay among modes, which reveals that pulse self-compression at longer wavelengths does not occur due to larger group velocity mismatch between the fundamental and higher-order modes for longer wavelengths [2]. Our study has important implications for the various fields of high-intensity nonlinear optics in gas-filled capillaries such as supercontinuum generation and high-order harmonic generation [3]. [1] L. Bergé et al., Phys. Rev. A 88, 023816 (2013). [2] G. Nagar and B. Shim, submitted. [3] T. Popmitchev et al. Science 336, 1287 (2012).  more » « less
Award ID(s):
2010365
PAR ID:
10346638
Author(s) / Creator(s):
;
Date Published:
Journal Name:
63rd Annual Meeting of the APS Division of Plasma Physics
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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