Plastic optical fiber lasers and amplifiers containing lanthanide complexes.

Organic dye-doped polymers have been widely investigated as gain media in solid-state dye lasers. Dye molecules which have large absorption and induced emission cross sections due to allowed π-π transitions are ideal active dopants for the generation and amplification of intense light pulses. However, continuous wave operation is not feasible with organic dyes because of the triplet losses. On the other hand, lanthanide ions that have long metastable state lifetimes are widely used in silica glass-based fiber amplifiers and for both continuous and pulsed lasers. It has been more than 30 years since the first lanthanide lasers were reported.1-3 During this period a wide variety of lanthanide lasers and amplifiers have been investigated, and extensive progress has been made by many researchers. Many reviews have been written concentrating primarily on the physical and chemical properties of lanthanides in many matrices for laser action.4-8 Recently, several books have focused on lanthanide-doped fiber amplifiers for optical communications.9-11 The success of lanthanide-doped fiber amplifiers has inspired thousands of publications and continues to motivate research on the many diverse components that are required in these systems. Optical links are now used primarily in applications such as telecommunications with single-mode silica optical fibers, which have the ability to provide high-bandwidth and long-distance communications. However, as the demand for bandwidth increases in the office and home, it has become increasingly important to develop very low cost optical links that can be readily installed by users. Plastic optical fibers (POF) have received increasing attention because of their clear technical advantages over glass fibers, such as flexibility and a large core diameter, which enables efficient connection and coupling resulting in a low-cost system for a local area network. Recently a low-loss (100 db/km), highbandwidth 5.12 GHz for 100 m transmission graded index plastic optical fiber (GI-POF) has been developed.12 Also, an all fluorinated POF, whose low loss region is extended to the visible and near-infrared, has been successfully prepared.13 Plastic optical fiber amplifiers (POFA) that generate signal light in the visible and near-infrared are potentially important because of their adaptability for POF-based short span optical local distribution networks. This review describes recent progress on plastic optical fiber lasers and amplifiers with lanthanides. We focus especially on the design and selection of plastic optical fiber and chelate materials.