Optical fibers, an important and promising material, have been the subject of intensive research and development due to their many scientific and practical applications. They are designed to guide light along its length by confining as much light as possible in its core. The interaction between the propagating light with the fiber material is the foundation of the development of various applications such as optical amplifiers, fiber lasers, sensors etc. The use and demand for optical fibers have grown in tandem with numerous new applications that have been continuously introduced by researchers and engineers