Excitation of Mode Groups in Multimode Fibers With the Aid of Diffractive Optics

In this letter, we report on the excitation of low order Laguerre-Gaussian mode groups with a common propagation constant in a multimode gradient index optical fiber. Enabling generic space-division multiplexer was based on a key multichannel diffractive optical element. The experimental results show integrity of the excited mode groups in an OM2 multimode fiber optic patch cord.