Abstract
The exact hybrid modes of a coreless optical fiber are calculated. Spatial distributions of electromagnetic fields near the cladding surface are obtained. A comparison of radial, azimuthal, and longitudinal field components near the cladding surface is performed for the hybrid exact modes and approximate linearly polarized (LP) modes. The polarization characteristics of the modes are studied taking into account the longitudinal field component depending on the type of hybrid modes and mode numbers. The combination of hybrid modes forms modes similar to LP modes, which have an almost uniform linear polarization inside the fiber far from the cladding surface. It is shown that under the cladding surface the polarization of LP-like modes is also linear, but significantly non-uniform in azimuthal angle with a deviation of the polarization angle by up to 21о from the main direction of mode polarization. In addition, the role of the longitudinal field component near the cladding surface increases significantly, where its value can exceed the values of the transverse components.