We report what is to our knowledge the first successful attempt in prism coupling a laser beam into a lithium niobate optical waveguide grown on a thermally oxidized (100) Si substrate by magnetron rf sputtering. Bragg x-ray diffraction, Rutherford backscattering, and birefringence measurements confirm that the sputtered films were nearly stoichiometric as well as highly textured lithium niobate. The refractive indices were nTE = 2.199 ± 0.002 and nTM = 2.263 ± 0.002. The lowest propagation loss in the waveguide was determined to be 1.9 ± 0.1 dB/cm at a wavelength of 633 nm.
© 1993 Optical Society of America
Original Manuscript: November 19, 1992
Published: May 15, 1993
Charles H. J. Huang and Thomas A. Rabson, "Low-loss thin-film LiNbO3 optical waveguide sputtered onto a SiO2/Si substrate," Opt. Lett. 18, 811-813 (1993)