Vectorial structural properties of truncated beam generated by Gaussian mirror resonator in the near field

Internal vectorial structure of the beam generated by the Gaussian mirror resonator (GMR) diffracted through a hard-edged aperture are evaluated in the near-field. Based on the vectorial angular spectrum representation of electromagnetic fields and the paraxial approximation, TE and TM terms of intensity distributions of the beam in the near field are derived in analytical forms, respectively. Numerical results reveal that the behaviors of TE and TM terms not only depend on the parameters of mirror resonators but also relate to the truncated parameter of the aperture. It is also shown that the distributions of TE and TM terms would not keep detached from each other because of the unorthogonality of their vectorial structures in the near field.

► Near-field TE and TM intensities of the beam generated by GMR are derived in analytical forms.
► It is revealed that TE and TM terms of the beam depend on resonator parameters and the truncated one.
► The near-field TE and TM terms are not detached from each other due to the unorthogonality of vectorial components.