Angle-resolved multioctave supercontinua from mid-infrared laser filaments

• Published in: Optics letters Vol. 41; no. 15; p. 3479
• Main Authors: Mitrofanov, A V, Voronin, A A, Sidorov-Biryukov, D A, Mitryukovsky, S I, Rozhko, M V, Pugžlys, A, Fedotov, A B, Panchenko, V Ya, Baltuška, A, Zheltikov, A M
• Format: Journal Article
• Language: English
• Published: United States 01.08.2016
• ISSN: 1539-4794
• DOI: 10.1364/OL.41.003479

Angle-resolved spectral analysis of a multioctave high-energy supercontinuum output of mid-infrared laser filaments is shown to provide a powerful tool for understanding intricate physical scenarios behind laser-induced filamentation in the mid-infrared. The ellipticity of the mid-infrared driver beam breaks the axial symmetry of filamentation dynamics, offering a probe for a truly (3+1)-dimensional spatiotemporal evolution of mid-IR pulses in the filamentation regime. With optical harmonics up to the 15th order contributing to supercontinuum generation in such filaments alongside Kerr-type and ionization-induced nonlinearities, the output supercontinuum spectra span over five octaves from the mid-ultraviolet deep into the mid-infrared. Full (3+1)-dimensional field evolution analysis is needed for an adequate understanding of this regime of laser filamentation. Supercomputer simulations implementing such analysis articulate the critical importance of angle-resolved measurements for both descriptive and predictive power of filamentation modeling. Strong enhancement of ionization-induced blueshift is shown to offer new approaches in filamentation-assisted pulse compression, enabling the generation of high-power few- and single-cycle pulses in the mid-infrared.