Determining the Relationship between the Amplitude Parameter and the Modal Power in Dual Mode Fibers

摘要

The theoretical description of linearly polarized (LP) modes in weakly guiding fibers includes an amplitude parameter which relates to source intensity and input conditions. As such, this parameter has direct bearing on the amount of power carried by individual modes. This paper derives the mathematical relationship between the power in the first two LP modes and their respective amplitude parameters. In subsequent experiments, this parameter is employed in conjunction with a measurement of the amplitude parameter to yield the modal power distribution in a dual mode fiber. Alternatively, if the power distribution is known by empirical means, the amplitude parameters can be determined to allow for accurate visualization of the propagating modes. This work allows for a better understanding of the operation of dual mode fibers in preparation for structural sensing.