Study on ultralow bending loss of bend-insensitive single mode optical fiber

Abstract

Abstract A novel bend-insensitive single mode fiber is proposed in this paper. A finite element method with a perfectly matched layer boundary is used to analyze characteristics of the mode field distribution, effective area and bending loss. To achieve the proposed fiber with a low bending loss, a symmetrical distribution of air holes on a doped trench is designed. The effects of structural parameters on the bending loss and effective area are discussed. The numerical results show that this structure can achieve a low bending loss and effective model area with smaller bend radius at a wavelength of 1550 nm. The bending loss is only 2.13 × 10−5 dB/m and the mode field diameter (MFD) is 8.71 μm, which can provide a good match with the single mode fiber (SMF). The simulation results show that the existence of air holes in the trenched layer can exist minimum point of bending loss with increasing the values of c, which is different from previous studies. Compared with a single mode fiber-28 (SMF-28) and a trench-assistant fiber (TAF), this structure still has an ultralow bending loss and a smaller effective area with a low-bend radius of 3 mm at a wavelength of 1550 nm. The proposed fiber may be preferable for optical connection.