Basic Studies Of Magneto-Optical Waveguide Devices

The optical communication system of the new generation drives the growing needs of communication devices in the industry, with the rapid development of the optical communication technology. The devices of optical communication are becoming function, micro, and integration. Magneto-optical waveguide devices, which have the magneto-optical nonreciprocal characteristics, own the advantages of high stability and realization of on-chip integration, playing an irreplaceable role in the development of optical communication.The purpose of this paper:Based on the magneto-optical nonreciprocal characteristics (MONC), research on the novel function and application of magneto-optical waveguide devices, and try to manufacture magneto-optical waveguide devices.1. Several magneto-optical waveguide devices based on MONC are proposed. The grating assisted magneto-optical nonreciprocal contradirectional coupler is proposed in the paper. Because of introducing magneto-optical nonreciprocal characteristics into the grating assisted contradirectional coupler, there is a deviation between the forward and backward reflection spectrums. This device can be used as isolator and circulator. The magneto-optical nonreciprocal director coupler is also proposed, which is designed by introduced magneto-optical nonreciprocal characteristics into the director coupler. The coupling length of forward is different to the one of backward, so this device can realize the functions of isolator and circulator. The necessary length of the device to realize these functions is reduced by optimizing the structure of the device. In addition, the paper pays attention to the grating which is the critical unit of many magneto-optical waveguide devices such as grating assisted magneto-optical nonreciprocal contradirectional coupler and magneto-optical waveguide grating. The author designs and fabricates a novel Bragg grating with periodically corrugation in the sides of silicon slab of SOI ridge waveguides, used to realize accurate control of narrow bandwidth with low side lobes by varying the distance between the slab grating region and the ridge and changing the extent of sidewall grating teeth.2. The application of magneto-optical waveguide devices in current sensors are demonstrated Based on the relationship between magnetic field and MONC. They are the current sensor based on grating assisted magneto-optical nonreciprocal contradirectional coupler, the current sensor based on magneto-optical nonreciprocal director coupler, and current sensor base on Mach-Zehnder interferometer utilizing magneto-optical nonreciprocal phase shift. These sensors utilizing the magneto-optical nonreciprocal characteristics, avoid the influence of reciprocal parameters, such as temperature and pressure, and improve the accuracy and stability of measurement.3. Several magneto-optical waveguides devices are fabricated utilizing the available laboratory condition. The author trys the trail produce of magneto-optical waveguide grating based on SOI and magneto-optical fiber, accumulating a great deal of experience through these experiments. The author also analyzes on the problems met in the experiments, and lays a solid foundation for the future experiments on magneto-optical waveguide devices.