Stimulated supercontinuum generation extends broadening limits in silicon
Abstract
We demonstrate that stimulated supercontinuum generation alleviates restrictions on spectral broadening in silicon waveguides. At telecommunications wavelengths, two-photon and free-carrier absorption typically deplete the pump before large broadening factors can be achieved. However, broadening via modulation instability (MI) can be enhanced by seeding, which also substantially improves the energy efficiency of spectral broadening in media with nonlinear loss. Coherent seeding also generates a stable output spectrum, in contrast to conventional approaches where broadening starts from noise. The combination of self-phase modulation and stimulated modulation instability generates broadening factors in excess of 40-fold at moderate intensity levels, with >15-times better energy efficiency.
- Publication:
-
Applied Physics Letters
- Pub Date:
- March 2012
- DOI:
- 10.1063/1.3692103
- Bibcode:
- 2012ApPhL.100j1111D
- Keywords:
-
- optical waveguides;
- self-phase modulation;
- silicon;
- spectral line broadening;
- supercontinuum generation;
- two-photon processes;
- 42.79.Gn;
- 42.65.Jx;
- Optical waveguides and couplers;
- Beam trapping self-focusing and defocusing;
- self-phase modulation