Stoichiometric lithium niobate for ultra-high performance optical waveguide devices

For a couple of decades, congruent lithium niobate (CLN) has been the choice electro-optic material for integrated optic modulators and switches. Despite the development of new substrates, such as electro-optic polymers and compound semiconductors,lithium niobate is still the preferred material for producing the highest performance commercial optical modulator and switch products. Today, stoichiometric lithium niobate (SLN) promises to further enhance the performance of these devices. Desirablecharacteristics such as sub-1 Volt switching voltage and bandwidth capability in excess of 100 GHz will be easier to achieve with SLN. This proposal addresses the production of highly stoichiometric lithium niobate wafers and the characterization of itsimportant material and optical properties. In addition, SLN wafers will be poled and optical waveguides produced in the poled samples. The optical properties of these waveguides will be characterized. Stoichiometric lithium niobate (SLN) is superior tocongruent lithium niobate (CLN) in all aspects of its material characteristics. In particular, SLN offers increased electro-optic coefficients, higher optical power handling capability and lower defects than CLN. It is predicted that the photonicsindustry will eventually replace CLN by SLN, in order to produce optical modulators with lower switching voltages and enhanced bandwidth.