| With the development of integration and miniaturization of devices as the main research trend,the research of micro nano photonics devices has attracted extensive attention of researchers.As an important waveguide structure in micro/nano photonics,microfiber has gradually become the main platform for various micro/nano photonics devices due to its low loss,simple fabrication method,strong optical field binding ability and strong evanescent field.As the fundamental device for achieving optical communication and fiber optic sensing networks,the research on optical phase modulation devices has also received great attention.At present,the research on phase modulation devices based on microfiber waveguide is still in its early stages,and the modulation medium used is relatively single.There is relatively little exploration and research on the modulation medium of modulators.At the same time,further optimization of the fiber optic interference structure is needed to enhance the integration of the system.Therefore,expanding the types of modulation media and improving the integration of microfiber modulation systems is of great significance for the development of microfiber phase modulation devices.In this thesis,various high integration microfiber phase modulation prototype devices based on different materials were designed and prepared,aiming to obtain microfiber phase modulators with excellent performance and high integration.The main research content of this article is as follows:1.All optical phase modulator based on gold nanorods(Au NRs)with localized Surface plasmon resonance(LSPR)effect integrated microfiber structure.Firstly,an all fiber phase modulator was prepared by integrating Au NRs with hollow suspended core fiber.808 nm was used as the pump light source,and the modulation efficiency of the device was experimentally tested to be 38 pm/m W.Then,in order to improve the performance,Au NRs was modified on the surface of thermal insulated microfiber by sol-gel film to prepare an optical phase modulator.The modulation efficiency of the modulator was 54.3 pm/m W,experimentally.Finally,the interference structure was optimized,and an all fiber phase modulator was constructed using a single interferometric microfiber integrated with Au NRs thin film to achieve all optical phase modulation.The modulation efficiency of the device was 64 pm/m W.2.Research on the preparation of an all optical phase modulator integrated with a single interferometric microfiber in two-dimensional materials.First,graphite oxide is integrated on the surface of interference microfiber to form a composite waveguide by chemical bond method,and 980 nm pump light is applied to achieve all-optical phase modulation.The experimental results show that the rising and falling edge times of the device are 3.7 ms and 1.5 ms,respectively.Subsequently,improvements were made to the integrated process to expand the available two-dimensional material types.Tungsten disulfide was successfully integrated on the surface of interferometric microfiber using a light induced growth method to prepare an all optical phase modulator,which was achieved through 980 nm pump light.3.A study was conducted on the preparation of an optical phase modulator integrated with a single interferometric microfiber in water,and a microfiber phase modulator based on the electro-optic effect of water was constructed.By applying voltage to regulate the orientation of water molecules at the charged interface,the phase modulation of the transmission spectrum is achieved by changing the refractive index near the tapered region of the microfiber.The modulation efficiency of the modulator is 3.17 nm/V for positive voltage and 17.44 nm/V for negative voltage.It not only has the advantage of compact structure of interferometric microfiber,but also has a low operating voltage range and bidirectional modulation ability of signal light phase.This paper focuses on the preparation of optical phase modulation devices for microfiber structure.A prototype device for microfiber phase modulation based on Au NRs,twodimensional materials,and water was designed and prepared,and experimental exploration was conducted on the preparation of phase modulators for a single interferometric microfiber.Through the above research,the selection of modulation media based on microfiber phase modulators has been broadened,and the foundation has been laid for the preparation of high integration fiber phase modulators.This research work has reference value and practical significance for understanding and mastering the mechanism and main output characteristics of phase modulation in microfiber. |
