Polarisation-independent low-power integrated acousto-optic tunable filter/switch using APE/Ti polarisation splitters on lithium niobate

A new polarisation-diversity integrated acousto-optic tunable filter/switch, incorporating passive Ti-indiffused waveguides and annealed proton-exchanged adiabatic X-junction polarisation splitters on XY lithium niobate, is demonstrated. The device requires only 11.2 dBm/channel of driving RF power. Switching characteristics at four 4 nm-spaced wavelengths are reported.