Generation of 3.6 ps optical pulses with repetition rate of 20 GHz using a high efficient electroabsorption modulator

This paper reports on stable generation of optical short pulses using an InGaAsP/InGaAsP strained multiple quantum well (MQW) electro-absorption (EA) modulator. Nearly transform-limited pulse trains with a narrowest pulse width of 3.6 ps are demonstrated by applying a 20 GHz sinusoidal voltage to the EA modulator. The MQW absorption layers in the EA modulator consist of tensile-strained wells and compressive-strained barriers, resulting in a large extinction efficiency of 20 dB/V, a small polarization sensitivity of 0.3 dB, and a high modulation bandwidth of 15 GHz.