Recent Advances in Microstructured Fibers for Power Delivery

Abstract

Abstract:We report recent advances in the development of fibers for the delivery of both single and heavily multimode laser beams in spectral regimes spanning the visible to mid-IR. IntroductionMicrostructured optical fiber (MOF) technology provides a powerful means to develop fibers with unique and enabling properties with potential uses spanning a very wide range of applications. Of all the opportunities provided by MOF technology amongst the most novel and intriguing are: (a) the possibility to guide light in air (through photonic band-gap or low density of state effects); (b) single mode guidance over extended spectral ranges (referred to as endlessly single mode (ESM) guidance); and (c) the fabrication of fibers with very much larger values of Numerical Aperture (NA) than possible using conventional fiber fabrication approaches. It is also important to realize that the MOF technology allows the fabrication of fibers using a single material -considerably enhancing the ease of producing fibers in new materials, such as polymers and compound glasses. This offers access to material properties that are substantially different to those of silica based glasses allowing, for example, fibers with transmission extending into the mid-IR, or ultrahigh values of nonlinearity per unit length. In the following sections we review recent progress in the design and fabrication of fibers that exploit several of these opportunities for the delivery of high power laser radiation and/or broadband light in different spectral regimes.