Electrooptical modulation in multiple quantum well hetero nipi waveguides

An optical intensity modulator based on multiple quantum well hetero (MQW-H) nipi waveguides is reported. In the low optical power regime (/spl sim/10/sup /spl minus/5/ W), the modulator exhibits an extinction ratio in excess of 100:1 at low drive voltage (4 V) and 5-B attenuation. Modelling and experimental results of the time response of the waveguide modulator are presented, and it is shown that the response is limited by the RC time constant of the drive circuit and the photocurrent charging up a dielectric capacitance. The modelling shows that with a loss penalty of /spl sim/1.5 dB, the speed of the present waveguide modulator is limited solely by the RC time constant that would allow modulation speeds of /spl sim/100 ps.<
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