KTN crystal with a large electro-optic effect and the potential for improving optical device performance

KTa/sub 1-x/Nb/sub x/O/sub 3/ (KTN) crystal exhibits an extremely large quadratic electro-optic effect, which makes it attractive for highly functional device applications. We have developed a crystal growth technology and successfully prepared 40 mm square KTN crystals. In addition, we have developed film growth and lithographic techniques for KTN crystal that can be used to fabricate an optical waveguide with excellent optical transmission performance. An optical switch using these KTN waveguides had a low driving voltage less than 1/10 that of conventional optical switches. In this workshop, we describe the crystal growth, material properties, waveguide fabrication, and device operation of KTN crystal.