GOALI: A comprehensive study of nonlinear phenomena in multimode optical fibers for enhancing the performance of optical communication systems

University Of Rochester, Rochester NY

Investigators

Abstract

Title: GOALI: A comprehensive study of nonlinear phenomena in multimode optical fibers for enhancing the performance of optical communication systems Abstract: The use of optical fibers for transmitting information over long distances has made the spread of the Internet possible. The advent of a technique, known as wavelength-division multiplexing, helped in increasing the capacity of fiber-based communication systems during the decades of the 1990s and 2000s. However, current systems will not be able to meet the continuing increase in the data rates fueled by such activities as on-line learning and video streaming. A new technique, called space-division multiplexing (SDM), is being studied in the laboratories worldwide to meet this demand. It makes use of optical fibers that are designed to support multiple spatial modes either by using a single large-size core or several narrower cores, each supporting a single mode. However, before the SDM technique can be implemented in real systems, it is necessary to understand the impact of various nonlinear effects occurring inside a multimode fiber, or a multicore fiber whose cores are coupled in view of their close proximity. This is what the proposed research project will accomplish. The main goal of the proposed research is to develop and implement new theoretical and numerical tools for modeling the simultaneous propagation of multiple data streams through SDM inside a multicore or a multimode fiber. These tools will be used to develop a fundamental understanding of how each SDM channel is affected by other co-propagating channels in the presence of various nonlinear effects such as self-phase modulation, cross-phase modulation, stimulated Raman scattering, and four-wave mixing. Even though the modes of an ideal fiber should not be coupled to each other, modes of any realistic multimode fiber will experience some random coupling. A major objective of this GOALI project is to understand the origin of this coupling and study how it impacts various nonlinear effects and the performance of SDM systems. In this effort, our industrial partner would be of immense help because of the recent experiments performed at Bell Labs that have quantified the extent of random mode coupling in six-mode fibers. The project has both the fundamental and applied aspects. An improved understanding of the nonlinear phenomena in multimode fibers is of fundamental importance and should help the next generation of graduate students and scientists in coming up with new device ideas. The study of nonlinear effects should also help in designing the future SDM systems. Two graduate students will work with the P.I. on this GOALI project as a part of their Ph.D. thesis. Both of them will spend time each year at the industrial site so that they can acquire valuable industrial experience. This kind of training of the graduate students is ideal for developing the work force for the U.S. telecommunication industry.