Picosecond all-optical switching using 1.55 /spl mu/m intersubband transition in an InGaAs/AlAs/AlAsSb coupled double quantum well (C-DQW) structure

Summary form only given. The intersubband transition (ISB-T) in quantum wells is attractive for the application to all-optical modulators and switches due to its ultrafast relaxation, large transition dipole moment, and widely tunable transition wavelength. Also, we have proposed the use of ISB-T in coupled double quantum well (C-DQW) structures to enable ultrafast all-optical switches operating at the communication wavelengths by utilizing enhanced electron-LO-phonon scattering in C-DQW. We show in the paper the first observation of picosecond all-optical switching based on the ISB-T at near-infrared wavelengths down to 1.55 /spl mu/m in an InGaAs/AlAs/AlAsSb C-DQW structure.