Generation of radiation tunable between 350 and 600 nm and nonlinear-optical spectral transformation of femtosecond Cr:forsterite-laser pulses in submicron fused silica channels of a microstructure fibre

An efficient generation of 350–600-nm wavelength-tunable radiation is experimentally demonstrated through nonlinear-optical frequency conversion of femtosecond Cr:forsterite-laser pulses in an array of submicron fused silica threadlike waveguiding channels in a microstructure fibre. Nonlinear-optical spectral transformation of femtosecond pulses in such waveguide channels gives rise to new isolated spectral components with frequencies exceeding the frequency of the third harmonic of pump radiation. Some of these new spectral components are separated from the central pump frequency by a frequency gap exceeding 580 THz.