Ultrafast silicon-based active plasmonics at telecom wavelengths

Jan N. Caspers, Nir Rotenberg, Henry M. van Driel
2010 Optics Express  
Using a gold/silicon grating coupler and modulating the silicon dielectric constant with 775 nm, 800 fs pump pulses we demonstrate an ultrafast spectral shift to a surface plasmon polariton coupling resonance for 1300-1700 nm probe pulses. With a modest pump fluence of 2.2 mJcm −2 the pump-induced free carriers shift the resonance by more than its width, with recovery occurring in 103 ps due to surface recombination.
doi:10.1364/oe.18.019761 pmid:20940871 fatcat:h7fvkanptfhbjjqoewdbafyrwy