| The twenty-first century is the era of information technology, optical has become the most advanced and important information carrier. With the expands of multimedia and Internet, the increasing demand has been presented for higher communication capacities and more quickly transmission speed, all optical communication has become the inevitable trend of communication development in future. As one of the most interesting branches of all-optical communication, the development potential of integrated optics is intriguing. It has become a mature subject; there are a wide range of related subjects, such as optics, optoelectronics, nonlinear optics, optical communications, and lasers. Optical waveguides, the basic elements of integrated photonic systems, have important research value which qualities are pivotal for the whole systems.Ion implantation is one of the most important techniques for modifying surface properties, and it has been widely used in many materials because it offers accurate control of both penetration depth and doping element by use of a particular species, as well as the energy of the ions. In addition ion implantation is not limited by the courier temperature of substrate materials. At present, a variety of waveguides can be obtained in many material systems, such as crystals with low curie temperatures, laser crystals, glasses, ceramic, polymer and semiconductors. It can fulfill selective implantation combined with mask technology and obtain many graph structure combined with other micro-processing method. As one of the dry etching technique, ion beam etching technique is a pure physics method so it could be applied to a wide range of optical materials. In both ion implantation and ion beam etching, the processing parameters can be accurately adjusted. Therefore, the fabrication process is highly reproducible, the relatively researches have potential application prospects.Optical waveguides are defined as high-refractive-index material surrounded by low-index layer. The refractive index profile (RIP) is very important for investigating the features of optical waveguides. It decides the waveguide properties such as guide mode and the nonlinear properties. For investigate the features of the waveguides, the precise index profile would be a basic problem. The relatively investigate will provide theory instruction for optical waveguide device.In this dissertation, we fabricate the planar, channel and ridge waveguide on the optical crystals by use of ion implantation combined with lithography and ion beam etching technique. The relative optical crystals include ferroelectric crystals (LiNbO3, Na:CBN), good nonlinear frequent doubling cystal (KTP), scintillators (ZnW04), laser crystals (Nd:SrGdGa3O7, Nd:YGG), sillenite crystal (BTO). The guided modes were detected using the prism coupling method. The RIP in the implanted waveguide region was reconstructed using the SRIM (the stopping and ranges of ions in matter) and RCM simulation packages. The formation mechanism of the waveguides was discussed. The propagation losses and near-field profiles of the light in the planar waveguide were measured by end-face coupling method. The FD-BPM was used to simulate the properties of waveguides and compared with the experiment results. The absorption and fluorescence spectrums of the part of the waveguide samples are investigated for obtain the relative information.Lithium niobate is a versatile material for its unique electro-optic, acousto-optic, photoelastic, photorefractive and nonlinear optic properties. LiNbO3 crystal waveguides are widely used in a variety of integrated optics devices, including switches, amplifiers, modulators and communications. A lot of research has been done on planar waveguides fabricated in LiNbO3 crystals by ion implantation and it has been relatively matured. The samples used in our work were z-cut congruent LiNbO3 wafers. The planar and channel waveguides were fabricated in z-cut CLN crystal by multiply energy and low dose ((2.2+1.8+1.6) MeV at a dose of dose of (3+2+1)×1014 ions/cm2) oxygen ion implantation. The photoresist mask consisted of narrow strips with a width of 5?m and a separation of 45?m or 6?m separately between adjacent channels. The end face of the channel waveguide was optically polished, and a microscope was used to observe the end face of the channel waveguide. We performed the end-face coupling measurement to obtain the near field optical intensity distribute of planar and channel waveguide. The FD-BPM (beam propagation method based on the finite difference method) was used to simulate the optical intensity distribution and used to contrast the results of end face coupling. The experiment results prove that the coupling effect is apparent in an array channel waveguide with a period of 11?m and this array can carry three FB bands. It also proves that the array channel waveguide can be made with lithography techniques and ion implantation. The results also imply that this design may be useful for discrete soliton-managed devices. Single crystals of z-cut LiNbO3 were implanted at room temperature using 3 MeV oxygen ions at a fluence of 5×1014 ions/cm2, the guided mode for waveguides experiencing different annealing conditions (as-implanted, 200?,300?,400?, and 500?for 30 min in air) were detected using the prism-coupling method; damage formation was investigated by the Rutherford backscattering spectrometry/channeling (RBS/C) method. The propagation losses and near-field profiles of the light in the planar waveguide were measured with an end-face coupling system.A new fabrication method for lithium niobate ridge waveguides is reported. Lithium niobate ridge waveguide with a smooth surface was fabricated by O+ ions implanted combined with Ar ion beam etching. The samples were implanted with 3MeV O+at a dose of 6×1014 ions/cm2. Ar ion beam sputtering with an energy of 500eV was used to etch the unshielded area of the planar waveguide for 3 hours. In the etching process, the ion beam, with an intensity of 25 mA/cm2 tilted 30°off the sample's normal direction and along the channels. To investigate the complete damage profile of the ion-implanted waveguide, the Ar ion beam etching method was used for mechanical stripping. The damage behaviour of the samples with different etching depths was studied using the RBS/C technique and we obtained the damage profile. For the ridge waveguide, the height of the ridge is measured through the use of Atomic Force Microscopy and a microscope with a reflected polarized light was also used to investigate the surface and end face. For the planar waveguide structure, the TM (transverse magnetic) guided mode before and after annealing at 633 nm was probed through prism-coupling measurements and the near field image was measured using an end-face coupling investigative method. The FD-BPM (Finite Difference BPM) was used to investigate the guided modes of the planar waveguide for comparison with the experiments results. The loss value of the ridge waveguide is about 2dB/cm. This method will used in fabricating integrated optics devices.Potassium titanyl phosphate (KTiOPO4, KTP) is one of the attractive nonlinear optical crystals for the frequency doubling. The double modes planar waveguide was formed by 2.4 MeV He ion implantation with the dose of 1.5×1016 ions/cm2. The optical properties were investigated by prism coupling and end-face coupling method. We fabricate the planar and ridge waveguide combined ion implantation with ion beam etching method at the implantation condition:6MeV Si ion at the fluence of 6×1014 ions/cm2. We made a series of annealing treatment from 250??550?for investigate the annealing properties of KTP planar waveguide. The planar waveguide can propagation the light of 633nm after proper annealing treatment. This indicates that annealing treatment will discover part of lattice damage and reduce propagation loss for this planar waveguide. For the ridge waveguide, the height of ridge was measured by a Stylus Profiler. Our method will provide a new way to fabricate ridge waveguide on KTP crystal.ZnW04 crystal is a kind of scintillators. We report on the optical properties of ZnWO4 planar waveguides created by ion implantation, and the effect annealing has on these structures. Planar optical waveguides in ZnWO4 crystals are fabricated by 5.0 MeV carbon ion implantation with a fluence of 1×1015 ions/cm2 or 500 keV helium ion implantation with the a fluence of 1×1016 ions/cm2. The thermal stability was investigated by 60 minute annealing cycles at different temperatures ranging from 260?to 550?in air. The reconstructed RIP includes a non-leaky guiding region which can confine the light efficiently. The near-field profiles of the TM mode for the samples were obtained, and they show good agreement between experimental and theoretical results. We obtained a single-mode ZnWO4 waveguide with a raised index at a wavelength of 1539 nm for the carbon implanted waveguide. The absorption spectra show that the implantation processes have almost no influence on the visible band absorption. The maximum value of?na(?na=0.0128 for a wavelength of 633 nm) was obtained by use of carbon ion implantation and proper annealing treatment. The annealing treatment results show that the planar waveguide formed by C ion implantation has a high thermal stability. Our data show that this waveguide fabrication technique could be of particular interest for optical waveguide devices on ZnWO4 crystals.Nd:SGG and Nd:YGG crystals have been identified as excellent laser materials. We report the formation of a planar waveguide in these laser crystals. The optical properties are measured by the prism coupling and end-face coupling methods. The propagation loss of Nd:SGG planar waveguide formed by C ion implantation is 0.84 dB/cm measured by back-reflected method, this result indicates that our waveguide has potential application value. The implantation processes had almost no influence on the absorption properties at the wavelength scale of w> 550 nm on account of the absorption spectrum for Nd:YGG waveguide. The microluminescence investigation reveals that, in the Nd:SGG and Nd:YGG waveguide, the fluorescence properties of the Nd3+ ions and the energy transfer efficiency were not deteriorated by the implantation process. Thus, the planar waveguides formed by the ion implantation method is a promising candidate in waveguide lasers. We implanted C ions into the x-cut Na:CBN crystal at the energy of 5MeV with the fluence of 1×105 ions/cm2 to obtain the planar waveguide. The results of prism coupling method indicate that the ne increased and no decreased waveguide structure was constructed. We performed end-face coupling arrangement and observed that it can propagate TM mode only. The barrier type waveguide was formed for no. The transmission ratio of CBN crystal is related to the polarization direction and this may correspondence to this phenomenon.Bi12TiO20 (BTO) crystals belong to a group of sillenites crystal. We report on the fabrication and characterization of optical-planar waveguides in Bi12TiO20 (BTO) crystals by O and He ion implantation.The loss value of the oxygen-implanted planar waveguide is reduced to 1.24 dB/cm after annealing at 260?for 30 min. The guided-mode profiles are successfully modelled through numerical simulations. The etch ratio of BTO crystal is 21 nm/min.We introduces a novel 1×4 branch optical splitter that was fabricated using multi-energy O+ ion implantation with standard lithography on a lithium niobate crystal. The design is of a cascade Y branch waveguide structure that equally distributes the input power between four output waveguides. The mask plate has a uniform main line, and all of the branches have a width of 5?m to simplify the fabrication process. The width of the structure after the 4 branches are completely divided is 75?m. The end-face of the four-branch waveguide was imaged by a microscope with reflected polarized light (Olympus BX51M, Japan). The results of the end-face coupling tests demonstrated that we successfully fabricated the power splitter, and the experiments agreed with the BPM simulations. The results also imply that potential photonic applications, such as optical interconnections, waveguide switches, and modulators, may be realized by using this design. |
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