Up to 40-Gb/s directly modulated laser operating at low driving current: Buried-heterostructure passive feedback laser (BH-PFL)

A directly modulated 1.55-m buriedheterostructure passive feedback laser exhibits a high modulation bandwidth of up to 34 GHz at moderate distributed-feedback (DFB) section currents between 20 and 60 mA. A very flat frequency response and a low alpha parameter have been demonstrated in the small signal modulation analysis. The device has open eyes at data rates of 25 and 40 Gb/s with reduced frequency chirp.