Anti-stokes Raman gain enabled by modulation instability in mid-IR waveguides

Sánchez, Alfredo D.
Fierens, Pablo Ignacio
Hernández, Santiago M.
Bonetti, Juan I.
Brambilla, Gilberto
Grosz, Diego
Título de la revista
ISSN de la revista
Título del volumen
"The inclusion of self-steepening in the linear stability analysis of modulation instability (MI) leads to a power cutoff above which the MI gain vanishes. Under these conditions, MI in mid-IR waveguides is shown to give rise to the usual double-sideband spectrum but with Raman-shaped sidelobes. This results from the energy transfer of a CW laser simultaneously to both stokes and anti-stokes bands in pseudo-parametric fashion. As such, the anti-stokes gain matches completely the stokes profile over the entire gain bandwidth. This remarkable behavior, not expected from an unexcited medium, is shown not to follow from a conventional four-wave mixing interaction between the pump and the Stokes band. We believe this observation to be of relevance in the area of Raman-based sensors, which, in several instances, rely on monitoring small power variations of the anti-stokes spectral component."