Photoluminescence enhancement of a silicon nanocrystal plane positioned in the near-field of a silicon nanowire

Semiconductor nanowires have an excellent ability to trap, guide, scatter or absorb light thanks to the presence of specific resonant optical modes. The electromagnetic field-enhancement associated to such effects can be used to modify the luminescence of emitters positioned in the vicinity of the nanowire, as to plasmonic nanoantennas. We show that the photoluminescence of silicon nanocrystals embedded in silica can be enhanced by a factor of about 3 in the presence of a silicon nanowire on the silica surface. This could be the basis of a promising CMOS-compatible process to improve silicon-based light emitting devices. 2D maps of the nanocrystal photoluminescence exhibit different behaviors as function of laser polarization and can be related to the electric field intensity distribution in the nanowire near-field, where the Si-NCs layer is located. Preliminary results of nonlinear optics for imaging the local electric field are presented.