Ultra-high four wave mixing efficiency in slot waveguides with silicon nanocrystals

We report on wavelength conversion through four-wave-mixing in silicon slot-waveguides with embedded silicon nanocrystals. The combination of strong optical confinement and Si:nc nonlinearity provides a huge waveguide nonlinear coefficient gamma = 1100 W(-1)m(-1). Moreover, the improvement in the fabrication procedure allowed a loss reduction with respect to previous reported structures, enabling the achievement of an extreme value for the conversion efficiency which represents the best result ever reported in the scientific literature. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3659694]