Supercontinuum generation under higher-order mode excitation in a microstructured fiber

The paper reports on the generation of a supercontinuum whose spectrum is partly divided between fundamental and higher-order modes. The mechanism leading to the continuum generation and the resulting spectrum are found to depend critically on the combination of the excited modes. In particular, multimode four-wave mixing with large wavelength separation between the Stokes and antiStokes bands is observed. This effect could be advantageously used, e.g. for wavelength conversion.