Wavelength discriminating optical switch

A novel wavelength discriminating bistable optical switch (WDOS) with completely optical input-output capabilities is presented. The WDOS is a three-terminal AlGaAs/GaAs n-p-n-p structure with an InGaAs/GaAs quantum well light emitting diode at the n-p junction. The WDOS can be switched to stable ON and OFF conditions by optical excitations at different wavelengths, which allows the use of a single optical window. The optical switching threshold can be adjusted by the external bias. Depending on the external bias, the WDOS functions as an optical inverter, an electrically programmable optical AND/OR gate, or an all-optical read-write memory element.>