Transmitted optical power through a tapered single-mode fiber under dynamic bending effects

This paper describes theoretically one of the physical phenomena that take place in a tapered single-mode optical fiber (taper): the transfer of optical power between different order modes. This optical power transfer depends on several factors; one of them is the static bending of the taper, as other authors have reported. In addition to these studies, we have noticed that if the bend angle oscillates, then the magnitude of the optical power transfer is also modified by other additional factors. Thus, at dynamic conditions the transmitted optical power through the taper is also affected by the oscillation frequency. Here we propose a more generic equation system to obtain the coupling coefficient between modes under static as well as dynamic bending conditions. When the presented equations are particularized for static conditions, a complete agreement with other studies is observed. In addition, validating the theoretical justification, some experimental results are also shown.