集成光学波导光栅研究进展

报道了20世纪80年代以来,研究组在集成光学波导光栅研究领域的主要工作及研究成果。其中包括集成光学波导光栅的制备研究;若干非线性波导光栅器件研究;高效体相位全息布拉格光栅-光导板的耦合互连;单片集成波导光栅波分复用等。这些研究工作为光通信、光计算、光传感和光学信息处理等应用领域提供小型化、低功耗、超快速全光型器件奠定了技术基础。

Research Progreess on Waveguide Gratings for Lntegrated Optics

From the 1980s,our main research results on waveguid grating domain of integrated optics are introduced as follows.The first, we designed and made Lloyd's simple versatile exposure interferometer.In the same installation, it can be formed by adjusting location of column lens to the straight stripe grating of the equal period, the chirped grating or the curve-grating masks on the photoresist, respectively. And then combining with ion or chemical etching technique, the various waveguid grating devices for integrated optics can be fabricated. The set up can also be used to fabricate volume holographic phase Bragg gratings with slant stripe by adjusting (angles) between sample and mirror. This Lloyd's exposure interferometer compared with traditional double-optical path exposure interferometer has the advantages, such as small-sized, versatile, a few of optical elements, shorter optical path, vibration-proof, small angle exposure and so on. So the technique by using Lloyd's exposure to make photoresist grating masks is called "standard technique", ane quoted abroad extensively. Up to now. grating devices have successfully been fabricated on varied waveguide materials, such as semiconductors, glasses, polymers and so on, by Lloyd's exposure and ion etching techinque. The second,some research results of the waveguide grating devices in our group since the year 1988 include: (1)The photoresist grating was made on parabolic coupling horns of channel waveguide with 4 μm width of K⁺-Na⁺ ion exchange CdS_xSe_1-x microcrystal glass to form grating limiter of 12 μJ limited energy threshold. (2) DFB optical bistability device was made on CdS_xSe_1-x microcrystal glass waveguide with K⁺-Na⁺ ion exchange by Lloyd's exposure and ion etching technique to obtain bistability switch time of 63 ps and threshold average powe of 77 mW. So devices operating with super fast rate and lower power loss were realized.(3)Chirped grating was made on K⁺-Na⁺ ion exchange CdS_xSe_1-x microcrystal glass wavequide by ion etching to form optical beam scanner. Maximum change quantity of focus location moving was 80 μm in power density of 1.5×10² W/cm² by using Ar ion laser of 0.514 5 μm wavelength. (4) Poly-layer ZnS/ZnSe thin film (clading) was alternatirely coated on BK7 glass waveguide of Ag⁺-Na⁺ ion exchange to form nonlinear waveguide grating device. Then optical interconnection with dynamic seek position characteristic with 3 cm linear space can be realized. (5) Interconnection coupling devices with volume holographic phase Bragg grating-light guided board were fabricated on photopolymer with red sensitive to form the grating-splitting board with equal intensity and successfully used for optical butterfly interconnection network of computer. (6)Volume (holographic) phase Bragg grating was fabricated on same glass light guided board to form optical interconnection of the spot to the spot with semiconductor laser 0.78 μm. Its potential application for optical interconnection (between) two printed was indicated. (7) Wavelength-division multiplexed device on monolithic integrated waveguide was made and measured to get complete separation of double-wavelength of 0.632 8 μm and 0.785 μm.