An optical fiber system that includes an in-fiber optic component powered by in-fiber light includes an optical fiber having a core, wherein the optical fiber propagates a sensing/signal light and a power light, with the sensing/signal light being propagated in the core. An optical transducing element, such as a layer of light absorbing material, is located in proximity to the in-fiber optic component. An optical tap region is provided in the optical fiber in proximity to the optical transducing element, and enables the power light to leak from the optical fiber and be absorbed by the optical transducing element. The optical transducing element converts the absorbed power light into a second energy form, such as heat, which is used to tune the in-fiber optic component.