High-speed wavelength-division multiplexing and demultiplexing using monolithic quasi-planar VCSEL and resonant photodetector arrays with strained InGaAs quantum wells

We demonstrate the high-speed (gigabit-per-second) operation of a wavelength-division-multiplexed optical interconnect, which is implemented by multiplexing the optical data from a multiple-wavelength vertical-cavity surface-emitting laser (VCSEL) array into a single optical fiber, and demultiplexing the composite data stream using an array of resonance-enhanced photodetectors (REPDs) with matching resonance wavelengths. By using VCSELs and REPDs with a new quasi-planar oxide-confinement design for improved high-speed performance, and using strained InGaAs-GaAs quantum wells to achieve a better tradeoff between optical responsivity and wavelength selectivity, wavelength-division-multiplexing (WDM) operation has been demonstrated under 1-Gb/s data modulation, with an optical crosstalk rejection ratio of better than -10 dB for wavelength channels that are spaced 4 nm apart.