Power transfer on multiple fiber couplers

Abstract

Fiber coupler is a great utilization that can be used to split one optical power to the more than two power outputs. Power transfer in fiber coupler depends on not only the geometry arrangement of the waveguides, but also the coupling coefficient. Power transfers between the waveguides are calculated using matrix transfer method. By introducing power input to the one of the waveguides, assuming cross section, power propagation, and fiber axis are held constants, at coupling constant coupling coefficient. It shows that coupling length of NX2, linear order NX3, and triangular NX3 fiber couplers are odd-multiple of z =p / 2k , z =p / 2k , and respectively. 2 2 z p k = If the coupling coefficient is varied along the coupling region, phase needed to transfer power to the others waveguide changes. The calculation of power transfer has been shown in 3D with variation of coupling coefficient from 0.1 mm-1 to 1.5 mm-1 . It describes that the higher the coupling coefficient, the shorter the coupling length or phase that required to transfer power completely to the others waveguides. The good agreement in minimum coupling length or minimum phase of NX2 and NX3 shows that the coupling length of linear order NX3 is larger with a factor 2 than the coupling length of NX2. However, the coupling length of triangular order NX3 is shorter with a factor 1/ 2 than the coupling length of NX2 fiber couplers.