Study the properties of metal-cladding nano-size optical fiber based on a new implementation of finite-difference time-domain

The properties of metal-cladding nano-size optical fiber are investigated using a new implementation of finite-difference time-domain, in which the amendment form of Drude is used. The results reveal that the thickness of Ag-film greater than 110 nm is enough to shield the interference between nano-size fibers when the wavelength of incident light is 632 nm. This proves that the metal-cladding nano fiber has stronger tight-confinement ability than the air-cladding nano fiber. Meanwhile, although the confinement ability of metal-cladding non-uniform fiber declines slightly with the angle α between fiber surface and horizontal plane, the metal-cladding fiber can solve the problem of light energy loss caused by diameter non-uniformity in transmission process greatly. The experimental results reveal that metal-cladding nano-size optical fiber can improve transmission efficiency greatly. The behavior of metal-cladding nano fiber demonstrated may provide actual reference value for the development of optical applications of nano fiber.