Differential Group Delay Estimation of Bent 2-Core Fibers Using An Approximate Solution

<p dir="ltr">In coupled multi-core fibers, the differential group delay (DGD) between cores is reduced. It is said that this is caused by the random-coupling. In this report, we interpret this phenomenon using an approximate solution of the coupled mode equations in the bent and twisted 2-core fiber. According to this picture, the input pulse wave for each core is converted into many small pulse waves. The group delay time (GD time) of each small pulse wave is calculated from the approximate solution. Moreover, applying the statistical properties to these GD times under fluctuations, distribution functions are generated. The DGD and pulse width are numerically calculated from these distribution functions. The numerical results have the same tendency as the simulations results.</p>