Intensity profile stabilities of high order vectorial modes of optical fibers

It is known that the high order vectorial modes of ideally circular optical fibers possess cylindrical symmetries in electric field distributions as well as intensity distributions. Unfortunately, the cylindrical symmetries may be disturbed by slight deformation of the fiber core in reality. In the present work we propose a method to evaluate the symmetries of intensity profiles of the high order vectorial modes of optical fibers. We firstly perform the numerical simulations of the intensity profiles of four vectorial modes within the LP11 mode group of the different fibers assuming the fiber core is deformed to be elliptical. Using the proposed method the symmetries and the stabilities of the intensity profiles of the modes are further deduced. It has been demonstrated that the symmetries of the modes are more sensitive to the deformation of the fiber core for fibers with smaller normalized frequencies. Furthermore, it is also concluded that for fibers with identical normalized frequencies the determined symmetries and stabilities of the modes appear to be different for different fiber configurations.