POLARIZATION SWITCHING IN ALGAAS GAAS DISTRIBUTED-FEEDBACK LASERS BETWEEN THE STABLE SINGLE LONGITUDINAL MODES/

TE/TM polarization mode switching is demonstrated in an AlGaAs/GaAs di stributed feedback laser diode. The device has two current injecting e lectrodes and as an active layer a conventional multiquantum well (MQW ) structure. A small amplitude modulation of the current into one of t he electrodes switches the polarization mode. Each mode corresponds to a stable single longitudinal mode of a distributed feedback laser. Th e lasing wavelength can be tuned continuously, without mode hopping, o ver 0.7 nm by controlling the total injection current. This new kind o f polarization switching is promising for optical switching systems an d optical frequency division multiplexing devices. (C) 1995 American I nstitute of Physics.