Electrooptic effects in an InGaAs/InAlAs multiquantum well structure

The field-induced refractive index change of an InGaAs/InAlAs MQW waveguide is examined for various wavelengths and TE/TM modes using a MZ modulator. The quadratic EO coefficients in the MQW waveguide for both TE and TM modes due to quantum confined Stark effect (QCSE) is on the order of 10/sup -18/ (m/sup 2//V/sup 2/), which is dominant compared with the linear EO effect. An effective linear EO effect, however, is significant because of the bias field arising from the built-in potential. This effect is more than one order greater than the conventional laser EO effect, which may suggest new device applications for QCSE.<
>