Research On Fabricating THz Waveguide

The research into plastic optical fiber already continues several decades'history. But it has not entered into the composition of optical fiber communi- cation because of its higher attenuation. In order to further reduce the attenuation of the fiber, we adopt one new fiber structure: hollow-core structure with cobweb cladding.The THz wave is the frontier of the electromagnetic spectrum which needs to exploit, and it located midway between microwaves and far red light. In recent years progress in THz wave generation and detection techniques has been enormous. Most of the THz wave systems rely on free space propagation because of the lack of transparent materials and low-loss wave guides. Our research purpose is to make use of the above new fiber structure, to choose one suitable material and wave guides for THz range. We decide to adopt a higher pure polyethylene as the material for fabricating THz wave guide by the comparison of many experiments.Besides excellent fiber structure, a set of large-scale, efficient tech- nological process for producing the fiber must be had, with the result that to raise the yield, to reduce the costs, and to become a good quality and low priced market product. For the new Bragg hollow-core fiber, if we adopt the processing methods of the past which prepare the preform firstly, and then from the perform to drawing the fiber with desired size, which not only take a lot of time and manpower, but also guarantee the quality hardly, as well as are unsuitable for the large quantity production. For these reasons, our laboratory adopts a process technology: one-step process, from raw material to the extrusion and forming, and through the drawing to give the finished fiber continuously. This process is simple and high efficient, very suitable for the materials with lower glass transition temperature such as plastics.So far, our experiment has obtained preliminary result, but not yet achieves the desired requirement. We except experiment research to make continuous headway in future.