  We show that single mode Si waveguides efficiently sustain high-speed
transmissions at 2 $\mu$m. We report the transmission of a 10 Gbit/s signal
over 7 cm with a power penalty below 1 dB. Parametric conversion in the
continuous wave regime is also demonstrated using the same waveguide structure
with a conversion window over 70 nm and an efficiency as high as-25 dB that can
be further increased in the pulsed pump regime.
