GaAs multiple-quantum-well reflector modulators with 4:l contrast ratios on Si
نویسنده
چکیده
Considerable modulation ratios are achieved for GaAs multiple-quantum-well reflector modulators grown on Si by inserting an AlAs/AlGaAs dielectric mirror into the device structure. Modulation ratios of up to 4: 1 is attained as the external bias voltage is increased to 9 V and the lC-1HH exciton absorption peak undergoes quantum-confirmed Stark shift. Measurements also indicate that cavity effects arising from the front surface reflection and that of the imbedded dielectric mirror strongly modify the reflectivity spectra.
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