Wavelength division multiplexed optical interconnects using femtosecond optical pulses

We demonstrate the operation of a multiple channel chip-to-chip wavelength division multiplexed (WDM) interconnect through a single fiber using GaAs diodes flip-chip bonded onto silicon. Multiplexing information onto a single fiber can minimize the high costs of fiber pigtailing, while avoiding time-division multiplexing circuits with their associated power consumption, latency, and very high-speed electronics. Additionally, traditional WDM systems use a separate laser for each channel. This increases both cost and complexity by requiring multiple sources and wavelength stabilization. We eliminate these concerns by using a mode-locked Ti:sapphire femtosecond laser as a broadband WDM source and employing the technique of "spectral slicing" to define our WDM channels.