Optical fibers containing nanoparticles were proposed twenty years ago to develop new applications in lasers and amplifiers. By encapsulating luminescent ions in the nanoparticles, new emission properties can then appear. However, the particles must be small in size to limit the optical losses by light scattering. More recently, this type of optical fiber has shown a strong potential for application as sensors. They exploit the light scattering property induced by nanoparticles. Then, the development of these fibers for these different applications depends on our ability to control the characteristics of the nanoparticles in the optical fibers. To reach this goal, we discuss how the drawing step is a crucial step to achieve this goal, i.e. to tune the size and the shape of the nanoparticles in the fibre. Through this approach, the characteristics of the nanoparticles are obtained in the as-drawn fiber, avoiding any additional post heat-treatment which may damage the optical fiber.
