15-GHz modulation performance of integrated DFB laser diode EA modulator with identical multiple-quantum-well double-stack active layer

Monolithically integrated InGaAsP 1.55-μm ridge waveguide distributed feedback laser diodes with an electroabsorption modulator using an identical active multiquantum-well (MQW) layer structure with two different QW types exhibit low-threshold currents <18 mA. The 3-dBe cutoff frequency of 200-μm-long modulators exceeds 15 GHz. 10-Gb/s transmission experiments with a voltage swing of 1.0 V/sub pp/ demonstrate the potential of this novel integration scheme.