Electro-optical effects in strain-compensated InGaAs/InAlAs coupled quantum wells with modified potential

摘要

We design and experimentally report strain-compensated InGaAs/InAlAs coupled quantum wells with modified potential. At a lower applied electric field (F(velence)50 kV/cm), the calculated blueshift of the lowest excitonic peak is 40.6 meV. In the room-temperature photocurrent experiments, a maximum upward shift of the apparent peak position of more than 35 meV is observed with an external reverse bias of -4 V. Furthermore, a lower absorption loss ((alpha)(velence)9.8 cm~(-1)) and a large negative refractive index change ((DELTA)n(velence)-0.0095) are obtained at 1.55 (mu)m. This indicates that the strain-compensated InGaAs/InAlAs coupled quantum wells with modified potential have a great potential for application to reflection type electro-optical switches.