Low voltage electroabsorption light modulator using an InGaAs/InP superlattice

Spectral transmission, reflection and photocurrent absorption results, obtained on gas source molecular beam epitaxy (MBE) grown InGaAs/InP multiple quantum wells (MQWs), and superlattice positive-intrinsic-negative (PIN) diode structures, demonstrate, for the first time in this materials system, that similar modulation to MQW structures can be achieved using superlattices, but at significantly lower operating voltages. Specifically, reflection changes of greater than 30% were observed for applied biases /spl lsim/ 4 V, in nonresonant modulators operating at a wavelength of 1.48 /spl mu/m. These results suggest the possibility of employing such devices in fast, high density optical modulator arrays operating over the 1.3 to 1.6 /spl mu/m range.<
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