Studying Of Light Propogation Property In The Metal-coated Fiber And The Taper Probe

The excellent transmitting property and the low cost of fiber had made it become one of the chief sustained technology of information society. The abroad application of nano-fiber and rapid development of technology has brought forward new problem of nano-fiber theory. Based on early work, this paper presents some research on the propogating theory of nano-fiber with metal-coated and the near-field solve of the probe. At first, we introduce the melting method of making fiber probe and draw tapered fiber using couple machine. A about 100 nanometer fiber probe with aluminium film on it was given by using vacuum deposition system. The mechanism of light transmitting in the metal-coated is analysed from complex dieletric constants in the visible light and near infrared wave band, based on the classic electronic theory. And then we analyse the mode theory of metal-coated fiber and make detailed analysis on the eigen equation and numeric solve according to Maxwell's equation. We get a set of equations to solve the field' s distribution based on the local model theory to analyse the evanescent field around the taper fiber. The advantage of this means is that it make the best use of the model theory of two layer step-index fiber, so the calculation of the near-field distribution around the taper fiber is more simple than the Green' s Function and the physical meaning is more evident than before.