LOW-DRIVE-VOLTAGE MQW ELECTROABSORPTION MODULATOR FOR OPTICAL SHORT-PULSE GENERATION

This paper reports on InGaAsP-InGaAsP tensile strained MQW electroabso rption (EA) modulators with a high modulation efficiency of 35 GHz/V t hat generate optical short pulses. We studied and optimized the multip le-quantum-well (MQW) structural parameters, barrier height, and well number, thickness, and strain in the absorption layer to ensure high a ttenuation efficiency and generate low duty cycle pulses. Low TE/TM po larization sensitivity was obtained by controlling strain, Stable, nea rly transform-limited optical pulse trains with a narrow pulsewidth of 3.6 ps are generated by applying a 20-GHz sinusoidal modulation volta ge (6 V-pp) to the EA modulator. This achieves a very small pulse duty cycle of 7.2%.