Modeling and optimized design of a parabolic-profile single-mode fiber with ultra-low bending loss and large-mode-area

• A novel parabolic-profile single-mode fiber with ultra-low bending loss and large-mode-area is investigated systematically.
• A performance index is defined as the ratio of bending loss to mode-field-diameter to evaluate fiber performance comprehensively.
• The proposed fiber could support both an ultra-low bending loss (0.052 dB/turn at bending radius of 5 mm) and a large effective mode area up to 260 μm2 at 1.55 μm, meanwhile maintaining cutoff wavelength at 1.26 μm.
• Compared to ITU-T G.657 series, the index PI of the proposed fiber is 327 times lower than that of an ITU-T G.652.D fiber with bending radius of 10 mm at operation wavelength of 1.55 m.PIPI

A novel parabolic-profile single-mode fiber with ultra-low bending loss and large-mode-area is proposed in this paper. A modified formula is derived for calculation of bending loss of parabolic-profile single-mode fiber and a performance index is defined as the ratio of bending loss to mode-field-diameter to evaluate fiber performance. The influences of fiber parameters on cutoff wavelength, bending loss and effective mode area are investigated systematically. Simulation results show that the parabolic-profile single-mode fiber could support both an ultra-low bending loss (0.052 dB/turn at bending radii R=5 mm) and a large effective mode area up to 260 μm2 at 1.55 μm, meanwhile maintaining single-mode operation rigorously (cutoff wavelength fixed at 1.26 μm). This fiber is suitable for compact, portable high power fiber-to-the-home applications.