Fabrication And Application Research Of Sub-wavelength Liquid-core Optical Fiber

This dissertation investigates the optical transmission property, preparation and application of sub-wavelength liquid-core optical fiber in both theory and experiment. First, the propagation and mode field property of such fiber is calculated, including propagation constant, electric field distribution, bending loss, dispersion and non-linear properties. This provides theoretical foundation for the applications of sub-wavelength liquid-core optical fiber.Then the fabrication of sub-wavelength liquid-core optical fiber is discussed in detail, that is, the tapering and packaging process. Sub-wavelength hollow-core fiber with diameter of 0.4～1μm and length of around 5 centimeters is successfully tapered using stripe heater. Then liquid is injected into the hollow-core fiber by capillary actions and gravity force and the fiber is cased in the Quartz glass tubes. Based on the above technique, liquid-core fibers of various inner diameters are prepared and optical propagation capability is verified by a laser diode.In the applications of liquid-core fiber, we mainly studied its potential applications in light propagation and non-linear field. The bending loss of liquid-core fiber is calculated to be one or two magnitude lower than that of conventional fiber. Then, we used liquid-core fiber in the study of Raman spectra. We innovatively used the mixtures of toluene and chloroform as the liquid core, and discovered that resonances of particle vibrations have an obvious impact on the output spectra. For instance, resonances of CH vibrations can enhance their scatterings and form a wide band of Raman gain. We believe this phenomenon should pave a new simple way for the supercontinuum generation and find its potential application in intermolecular science. Finally we theoretically simulated the application of sub-wavelength liquid-core optical fiber in supercontinuum generation and polarization control.The innovation of this article is the combining of sub-wavelength fiber and liquid-core fiber, proposing the concept of sub-wavelength liquid-core fiber. This kind of fiber combines the merits of both sub-wavelength fiber and liquid-core fiber. It may find potential applications in sensing, non-linear optics, optical propagation, high-density optical integration and optical communication.