The work reports for the first time on fibre-based Raman conversion with relatively large Stokes shift pumped by double-scale laser pulses having various degree of coherence. It was discovered that the degree of coherence of the pump pulses affects significantly the amount of the wavelength shift, intensity, and spectral width of frequency-downconverted radiation. At lower coherence within double-scale pulses, the magnitude of intra-pulse femtosecond field oscillation grows, leading to stronger nonlinear pulse interaction with the optical medium. This discovery suggests new approaches to nonlinear transformation of partially coherent laser pulses, typical of many mode-locked generation regimes of fibre lasers.

Date Published: 4 March 2019
PDF: 6 pages
Proc. SPIE 10902, Nonlinear Frequency Generation and Conversion: Materials and Devices XVIII, 109021F (4 March 2019); doi: 10.1117/12.2509750

Published in SPIE Proceedings Vol. 10902:
Nonlinear Frequency Generation and Conversion: Materials and Devices XVIII
Peter G. Schunemann; Kenneth L. Schepler, Editor(s)