Demonstration of a compact bilayer inverse taper coupler for Si-photonics with enhanced polarization insensitivity.

We demonstrate a compact (30 μm long) broadband bilayer inverse taper edge-coupler for silicon photonics with a 1.7 dB coupling loss from a commercially available focused fiber with 5 μm mode diameter. We compare the performance of our bilayer taper with a conventional SOI inverse taper coupler and show that our bilayer coupler achieves between 1.

Ultrafast silicon-based active plasmonics at telecom wavelengths.

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 mJ cm(-2) the pump-induced free carriers shift the resonance by more than its width, with recovery occurring in 103 ps due to surface recombination.