Segmented subwavelength silicon gratings manufactured by high productivity microelectronic technologies for linear to radial/azimuthal polarization conversion

Thomas Kämpfe (1) , Pierre Sixt (2) , Denis Renaud (2) , Armelle Lagrange (2) , Fabrice Perrin (2) , Olivier Parriaux (1)

1 LHC - Laboratoire Hubert Curien
2 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information

A polarization rotation is realized by subwavelength binary gratings, where the round trip phases of the smallest grating modes are fixed to the smallest possible integer numbers of 2π allowing a phase difference of π between TE and TM polarizations and almost 100% transmission. The principle is applied to a polarization transformation in the 1030 to 1064-nm wavelength range, using a segmented polarization rotating element converting a linearly polarized incidence to a radial or azimuthal polarization distribution. The elevated costs of such kinds of polarization transformers based on assembled birefringent crystals are avoided by using mass-fabrication compatible silicon-on-insulator technology on a wafer scale. It shows the general potential of microelectronic technology, concerning the batch manufacturing of wavelength-scale diffractive, grating-based elements for processing free space waves.

Mots clés: polarization conversion; subwavelength grating; effective index; radial polarization; azimuthal polarization; silicon-oninsulator

Domaines: Optique [physics.optics]

Thomas Kämpfe, Pierre Sixt, Denis Renaud, Armelle Lagrange, Fabrice Perrin, et al.. Segmented subwavelength silicon gratings manufactured by high productivity microelectronic technologies for linear to radial/azimuthal polarization conversion. Optical Engineering, 2014, 53 (10), pp.107105. ⟨10.1117/1.OE.53.10.107105⟩. ⟨hal-01174133⟩