Polymer nanowires are used in the fabrication of light-emitting devices, optical waveguides, optical switches, ultra-high sensitivity nanosensors and other devices taking advantage of their flexibility and other unique properties. However fabrication of the nanowire itself is not easy. Researcher Masahiro Goto and Group Leader Masahiro Tosa, Materials Reliability Center, National Institute of Materials Science have succeeded in fabricating Polymer Nanowires using Pulsed Laser. This extremely simple formation of polymer nanowires with different sizes and lengths was possible by a dry process in the atmosphere. Polymer nanowires are formed when a polymer film containing dispersed organic molecules is subjected to convergent irradiation by a pulsed laser with optimized light intensity. In this process a polymer film which serves as the material for the wire wasprepared. Molecules which absorb laser light (for example, organic molecules such as coumarin, perylene, etc.) are dispersed in this film. When the film is subjected to one pulse of convergent irradiation by pulsed laser light (e.g., wavelength: 440nm, pulse width: 900ps) using objective lens, it was found that the molecules are excited, and an extremely fine polymer nanowires (diameter: 5-200nm, length: 10-2000μm; controlled depending on the conditions) are formed by this energy. The formation time was approximately 1μs, and it was possible to form all of the polymer nanowires (PMMA, PEMA, PBMA, polystyrene) which have been attempted to date.