Integrated optical, wavelength selective, acoustically tunable 2×2 switches (add-drop multiplexers) in LiNbO/sub 3/

Fully packaged, polarization independent, integrated acoustooptic 2/spl times/2 switches have been developed which can be also used as add/drop multiplexers. The devices have been fabricated in X-cut Y-propagating LiNbO/sub 3/ and can be operated at wavelengths around 1550 nm. They consist of passive polarization splitters and acoustooptic TE-TM converters with weighted coupling. A filter bandwidth of 2.0 nm and a tuning range of 130 nm have been obtained. The fiber-to-fiber insertion loss is <4.6 dB and a residual polarization dependence of 1.3 dB for bar-state and 0.1 dB for cross-state routing has been achieved.