Enhanced stimulated Raman scattering in silicon nanocrystals embedded in silicon-rich nitride/silicon superlattice structures

In this paper, we report on the observation of stimulated Raman scattering in amorphous silicon nanocrystals embedded in Si-rich nitride/silicon superlattice structures SRN/Si-SLs. In particular, we have experimentally demonstrated amplification of Stokes signal up to 0.9 dB/cm at 1540.6 nm using a 1427 nm continuous-wavelength pump laser, consistent with a preliminary valuation of approximately a fourfold enhancement of the gain coefficient in Raman amplifier based on SRN/ Si-SLs with respect to silicon. Finally, a significant reduction in threshold power of about 40% is also reported. Our findings indicate that silicon nanocrystals embedded in Si nitride-based superlattice structures show great promise for Si-based Raman lasers. © 2008 American Institute of Physics. DOI: 10.1063/1.3050109