Specialty Optical Fibers Handbook

diameters, so this mode couples very well with a linearly polarized input laser

beam. The flux distribution for the HE

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mode shown in Fig. 10.8(c) is somewhat

elongated in the direction parallel to the axis of polarization of the mode. Note,

however, that for fibers with larger cores (radius larger than 30a or so), this

asymmetry becomes much less pronounced and the flux distribution becomes

almost azimuthally symmetric. The TE

01

mode is a nondegenerate azimuthally

symmetric mode for which the electric field is always oriented in the azimuthal

direction, as can be seen in Fig. 10.8b. This property, together with the boundary

condition at the interface ...