Stacked-diode electroabsorption modulator

We present a n-i (multiple quantum well [MQW])-p-i(MQW)-n device wherein the n contacts are tied together and biased with respect to the p contact to form an electroabsorptive modulator. Since the light passes through both MQWs large electroabsorption is obtained with lowered voltages since the field is applied in parallel to both MQWs. In particular, wide optical bandwidth is obtained at moderate voltages since high fields may be applied resulting in large Stark shifts of the MQWs. We measure a change in reflectivity greater than 40 percent over a optical bandwidth of 20 nm for 0-14 volts operation.<>