We report the near-stoichiometric Ti：LiNbO3 strip waveguides fabricated by vapour transport equilibration （VTE） at 1060~^{／circ}C for 12 h and co-diffusion of 4--8~／mu m wide, 115-nm thick Ti-strips. Optical stud...We report the near-stoichiometric Ti：LiNbO3 strip waveguides fabricated by vapour transport equilibration （VTE） at 1060~^{／circ}C for 12 h and co-diffusion of 4--8~／mu m wide, 115-nm thick Ti-strips. Optical studies show that these waveguides are monomode at 1.5~／mu m and have losses of 1.3 and 1.1~dB/cm for the TM and TE modes, respectively. In the waveguide width/depth direction, the mode field follows a Gauss/Hermite--Gauss profile. A secondary ion mass spectrometry study reveals that the Ti profile follows a sum of two error functions along the width direction and a complementary error function in the depth direction. Micro-Raman analysis shows that the Li-composition in the depth direction also follows a complementary error function. The mean Li/Nb ratio in the waveguide layer is about 0.98. The inhomogeneous Li-composition profile results in a varied substrate index in the guiding layer, and the refractive index profile in the guiding layer is given.展开更多
In this paper, damages and annealing effects of X,Y and Z cut LiNbO-3 implanted by 350keV high energy Ti (1.5 x 10<sup>17</sup> / cm<sup>2</sup>) are studied. The surface damages of X,Y cut pla...In this paper, damages and annealing effects of X,Y and Z cut LiNbO-3 implanted by 350keV high energy Ti (1.5 x 10<sup>17</sup> / cm<sup>2</sup>) are studied. The surface damages of X,Y cut plates are nearly amorphous, but the surface damage of Z cut does not reach saturation. Radiation damage is mainly due to Nb moving atoms and Ti atoms occupy the interstitial sites. By annealing the sample at 1000℃, most damage is removed from the boundary between implanted layer and LiNbO<sub>3</sub> base to surface.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 50872089 and 60577012)the Research Grants Council of the Hong Kong Special Administrative Region, China (Grant No. CityU 1194/07)
文摘We report the near-stoichiometric Ti：LiNbO3 strip waveguides fabricated by vapour transport equilibration （VTE） at 1060~^{／circ}C for 12 h and co-diffusion of 4--8~／mu m wide, 115-nm thick Ti-strips. Optical studies show that these waveguides are monomode at 1.5~／mu m and have losses of 1.3 and 1.1~dB/cm for the TM and TE modes, respectively. In the waveguide width/depth direction, the mode field follows a Gauss/Hermite--Gauss profile. A secondary ion mass spectrometry study reveals that the Ti profile follows a sum of two error functions along the width direction and a complementary error function in the depth direction. Micro-Raman analysis shows that the Li-composition in the depth direction also follows a complementary error function. The mean Li/Nb ratio in the waveguide layer is about 0.98. The inhomogeneous Li-composition profile results in a varied substrate index in the guiding layer, and the refractive index profile in the guiding layer is given.
文摘In this paper, damages and annealing effects of X,Y and Z cut LiNbO-3 implanted by 350keV high energy Ti (1.5 x 10<sup>17</sup> / cm<sup>2</sup>) are studied. The surface damages of X,Y cut plates are nearly amorphous, but the surface damage of Z cut does not reach saturation. Radiation damage is mainly due to Nb moving atoms and Ti atoms occupy the interstitial sites. By annealing the sample at 1000℃, most damage is removed from the boundary between implanted layer and LiNbO<sub>3</sub> base to surface.
