Experimental Analysis of Stress Induced Mode Coupling in a 50 μm Graded Index Multi Mode Fiber

We are investigating the effects of mechanical stress on the mode coupling within a 50 μm Graded Index Multi Mode Fiber. The linear transmission effects in the fiber are investigated by measuring the power transfer matrix for the first five mode groups. Our results show that a defined mechanical stress applied to the primary coating on a short section of the optical fiber leads to a reproducibly increasing cross talk between the investigated mode groups.