The role of the inverse Cherenkov effect in the formation of ultrashort Raman solitons in silica microspheres

We theoretically demonstrate a new regime of the formation of ultrashort optical solitons in spherical silica microresonators with whispering gallery modes.The solitons are driven by a coherent CW pump at the frequency in the range of normal dispersion, and the energy is transferred from this pump to the solitons via two channels: Raman amplification and the inverse Cherenkov effect. We discuss three different regimes of soliton propagation and we also show that these Raman solitons can be controlled by weak coherent CW signals.