Electric-field-induced refractive index variation in quantum-well structure

The refractive index variation in a quantum-well structure by an electric field is given theoretically. The calculated variation is −1% for an applied field of 3.1×105 V/cm in a 300 Å-thick GaInAsP/InP single quantum well, which is about 39 times larger than the bulk value. A semiconductor quantum-well structure is found theoretically to be a new material with a larger electro-optic coefficient. Application to a new optical switching device is also suggested.