Degenerate intermodal four-wave mixing with Q-switched nanosecond pulses in SMF-28 for the generation of discrete ultraviolet-visible wavelengths

Abstract

Intermodal four-wave mixing (IMFWM) is demonstrated in a standard SMF-28e + fiber through pumping in the normal dispersion regime by a Q-switched nanosecond pulsed laser. A new IMFWM process where two pump photons in LP01 mode are completely annihilated to give rise to Stokes and anti-Stokes photons, both in LP02 mode, has been observed. Discrete ultraviolet peaks at 390.7 nm and 396.7 nm are also observed in this communication fiber through a complex cascaded process.