The suitability of SiGe multiple quantum well modulators for short reach DWDM optical interconnects

We describe calculations that address the suitability at using silicon-germanium multiple quantum well (MQW) modulators in dense wavelength division multiplexed (DWDM) short reach optical interconnects that vary over a significant temperature range. Our calculations indicate that there is a tradeoff between the number of channels, the temperature range and laser power required. Twenty to forty DWDM channels at 100 GHz and 50 GHz channel spacing is possible in DWDM links with a ~ 12° temperature range with less than a 1 dB laser power penalty compared to the optimum single channel, single temperature case. The same number of channels can be operated over a wider 37° temperature range with laser power penalties of 3 dB. It shows that, even for DWDM systems, silicon-germanium modulators might provide an alternative to ring and disk resonant modulators without the need for stringent (<< 1 °C) temperature control.