Materials Development for Advanced Optical Fiber Sensors and Lasers

Beyond their utility for all modern communications, glass optical fibers are of significant additional present and future value for defense, sensor, and manufacturing systems. However, the extreme commercial scale of communication optical fibers has relegated these special applications to a niche dual-use industry. Accordingly, optical fibers are variations on a commercial theme and, generally, do not adequately address more extreme performance defense and sensor demands. Making matters worse, the majority of present global research into optical fibers has focused on geometric microstructuring in order to force the light to behave counter its natural inclinations. As a result, today’s “highestperformance” microstructured optical fibers (MOFs) and photonic crystal fibers (PCFs) are remarkably complex in their structures. Accordingly, their costs are significant and their availability is limited. This chapter reviews the state of knowledge of next-generation optical fibers whose properties arise from attacking performance limitations at their fundamental origin: the interaction of the light with the material through which it propagates. The chapter is divided into two general themes: (1) intrinsically low optical nonlinearities of critical need for high-power and narrow line-width laser applications and (2) novel material effects of interest to sensing. In each case, the material considerations are first introduced, followed by a literature survey of some best results to date. A discussion then is provided that relates to the impact of such materially engineered fibers on specific laser and sensor applications followed by opportunities for further research.