The refractive index profiles of 3 MeV O^2＋ ion-implanted planar waveguides in lithium niobate are reconstructed based on etching and ellipsometry techniques. SRIM2003 code is used to simulate the damage distribution...The refractive index profiles of 3 MeV O^2＋ ion-implanted planar waveguides in lithium niobate are reconstructed based on etching and ellipsometry techniques. SRIM2003 code is used to simulate the damage distribution in waveguide. It is demonstrated that the index profile of this kind of waveguide, extending to several micrometres in depth, can be determined by etching in combination with following ellipsometric measurements. A good agreement is found between the simulated damage distributions in waveguide and the index profiles based on experimental data, and the width of refractive index barrier is wider than the result of SRIM2003.展开更多
Cs^＋-K^＋ ion exchanges are performed on z-cut KTiOPO4 crystals with chromium coating covered. The temperature of ion exchange is 430℃, and the time range from 15min to 30min. The dark mode spectra of the samples ar...Cs^＋-K^＋ ion exchanges are performed on z-cut KTiOPO4 crystals with chromium coating covered. The temperature of ion exchange is 430℃, and the time range from 15min to 30min. The dark mode spectra of the samples are measured by the prism coupling method. The channel structures on the samples are observed by a microscope and the near field pattern of the channel waveguides are measured by the end-fire coupling method. The refractive index of the samples increases and the increments at surface are modulated due to the existence of Cr film. In the region covered by Cr film, the refractive index of the samples at the surface increases dramatically in a shallow layer. The results of energy dispersive x-ray spectra indicate that in the region covered with Cr film, Cr ions participate in the ion exchange process, and enhance the refractive index. The results may provide a possibility that achieves index enhancement and Cr doping synchronically.展开更多
The optical waveguide was formed on an LiNbO_(3) substrate by 2.6 MeV nickel ions implantation to the dose of 9×10^(14) ions/cm^(2).Five dark modes were observed by the prism coupling technique.The refractive ind...The optical waveguide was formed on an LiNbO_(3) substrate by 2.6 MeV nickel ions implantation to the dose of 9×10^(14) ions/cm^(2).Five dark modes were observed by the prism coupling technique.The refractive index profile was obtained by using the reflectivity calculation method.A large index decrease was found in the guiding region and in the optical barrier,which is somewhat different from that of the LiNbO_(3) waveguide formed by the MeV He+ions.The position of the optical barrier is deeper than that of the damage peak calculated by TRIM'90(Transport of Ions in Matter)code.The crystal lattice damage in the guiding region caused by the Ni+ion implantation was analysed by the Rutherford backscattering/channelling technique.展开更多
The diffusion behaviour of 1.0 and 2.0MeV Au^(+)implanted into LiB_(3)O_(5)single crystal has been studied by the Rutherford backscattering of 2.1 MeV He ions.Annealing was performed at temperatures of 600,700,and 800...The diffusion behaviour of 1.0 and 2.0MeV Au^(+)implanted into LiB_(3)O_(5)single crystal has been studied by the Rutherford backscattering of 2.1 MeV He ions.Annealing was performed at temperatures of 600,700,and 800℃each for 30 min.The results show that the diffusion behaviour is quite different in two cases.In LiB_(3)O_(5),the depth distribution of the 1.0MeV Au is nearly Gaussian and becomes bimodal after annealing at 800℃for 30 min.But in the case of 2.0 MeV,the depth distribution of as implanted Au^(+)in LiB_(3)O_(5)has splitting behaviour.After 800℃for 30 min annealing,there is no obvious diffusion observed.The precise interpretation is needed.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 10735070. We would like to thank Professor Ke-Ming Wang at Shandong University for helpful discussion. We also thank Dr Hong-Ji Ma and Rui Nie at Peking University for their help in ion implantation.
文摘The refractive index profiles of 3 MeV O^2＋ ion-implanted planar waveguides in lithium niobate are reconstructed based on etching and ellipsometry techniques. SRIM2003 code is used to simulate the damage distribution in waveguide. It is demonstrated that the index profile of this kind of waveguide, extending to several micrometres in depth, can be determined by etching in combination with following ellipsometric measurements. A good agreement is found between the simulated damage distributions in waveguide and the index profiles based on experimental data, and the width of refractive index barrier is wider than the result of SRIM2003.
文摘Cs^＋-K^＋ ion exchanges are performed on z-cut KTiOPO4 crystals with chromium coating covered. The temperature of ion exchange is 430℃, and the time range from 15min to 30min. The dark mode spectra of the samples are measured by the prism coupling method. The channel structures on the samples are observed by a microscope and the near field pattern of the channel waveguides are measured by the end-fire coupling method. The refractive index of the samples increases and the increments at surface are modulated due to the existence of Cr film. In the region covered by Cr film, the refractive index of the samples at the surface increases dramatically in a shallow layer. The results of energy dispersive x-ray spectra indicate that in the region covered with Cr film, Cr ions participate in the ion exchange process, and enhance the refractive index. The results may provide a possibility that achieves index enhancement and Cr doping synchronically.
基金Supported by the National Natural Science Foundation of China under grant No.19875032Natural Science Foundation of Shandong Province.
文摘The optical waveguide was formed on an LiNbO_(3) substrate by 2.6 MeV nickel ions implantation to the dose of 9×10^(14) ions/cm^(2).Five dark modes were observed by the prism coupling technique.The refractive index profile was obtained by using the reflectivity calculation method.A large index decrease was found in the guiding region and in the optical barrier,which is somewhat different from that of the LiNbO_(3) waveguide formed by the MeV He+ions.The position of the optical barrier is deeper than that of the damage peak calculated by TRIM'90(Transport of Ions in Matter)code.The crystal lattice damage in the guiding region caused by the Ni+ion implantation was analysed by the Rutherford backscattering/channelling technique.
基金Supported by the National Natural Science Foundation of China under Grant No.19775031,the Hong Kong University of Science and Technology Research Infracture Grant R191/92SC05Laboratory of Heavy Ion Physics,Peking University。
文摘The diffusion behaviour of 1.0 and 2.0MeV Au^(+)implanted into LiB_(3)O_(5)single crystal has been studied by the Rutherford backscattering of 2.1 MeV He ions.Annealing was performed at temperatures of 600,700,and 800℃each for 30 min.The results show that the diffusion behaviour is quite different in two cases.In LiB_(3)O_(5),the depth distribution of the 1.0MeV Au is nearly Gaussian and becomes bimodal after annealing at 800℃for 30 min.But in the case of 2.0 MeV,the depth distribution of as implanted Au^(+)in LiB_(3)O_(5)has splitting behaviour.After 800℃for 30 min annealing,there is no obvious diffusion observed.The precise interpretation is needed.
