Second harmonic generation in GaP photonic crystal waveguides
  We demonstrate enhanced second harmonic generation in a gallium phosphide photonic crystal waveguide with a measured external conversion efficiency of 5$\times10^{-7}$/W. Our results are promising for frequency conversion of on-chip integrated emitters having broad spectra or large inhomogeneous broadening, as well as for frequency conversion of ultrashort pulses. 
Kelley Rivoire, Sonia Buckley, Fariba Hatami, Jelena Vuckovic
physics.optics