Far-field divergence of vectorial structure of a Gaussian beam

In the far-field, the Gaussian beam is composed of the TE and TM terms. Moreover, the TE and TM terms of a Gaussian beam are orthogonal to each other. The analytical and concise expressions of the TE and TM terms are derived in the far-field. The expressions of the energy flux distributions of the TE term, the TM term, and the whole Gaussian beam are also presented in the far-field. The ratios of the power of the TE and TM terms to that of the whole Gaussian beam are examined in the far-field. Also, the far-field divergence angles of the TE term, the TM term, and the whole Gaussian beam are derived without any approximation. The inverse of the product of the wavenumber and the Gaussian beam waist is defined as the f-parameter. The influences of the linearly polarized angle and the f-parameter on the far-field divergence angles of the TE term, the TM term, and the whole Gaussian beam are discussed in detail.