A monolithic multiplexed 16-wavelength WDM transmitter with accurate channel spacing

We demonstrate direct modulation results on a 16-channel chirped multifrequency laser without a shared amplifier. There is no optical power penalty compared to the case of a single modulated channel when all 16 channels are modulated simultaneously at 310 Mbps, and 2 dB power penalty when they are are modulated at 622 Mbps due to electrical crosstalk. The entire wavelength comb can be shifted by 275 GHz by changing the device temperature from 13 to 33C while the channel-to-channel power uniformity remains better than 0.2 dB and the optical channel spacing stays exactly 200 GHz.