Linear to radial/azimuthal polarization converter in transmission using form birefringence in a segmented silicon grating manufactured by high productivity microelectronic technologies

Thomas Kampfe (1) , Pierre Sixt (2) , Denis Renaud (3) , 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
3 SDOT - Services des Opérations Technologiques

A polarization rotation is realized by subwavelength binary gratings, where the TE and TM round trip phases of the smallest grating modes are fixed to the smallest possible integer numbers of 2pi that allow a straight-through phase difference of pi This results in a subwavelength grating allowing to realize a half-wave element of almost 100% transmission. The principle is applied to a polarization transformation in the 1030-1064 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 kind 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 transformation; subwavelength grating; effective index; radial polarization; azimuthal polarization; silicon on insulator

Domaines: Optique [physics.optics]

Thomas Kampfe, Pierre Sixt, Denis Renaud, Armelle Lagrange, Fabrice Perrin, et al.. Linear to radial/azimuthal polarization converter in transmission using form birefringence in a segmented silicon grating manufactured by high productivity microelectronic technologies. SPIE Photonics Europe, Micro-Optics Conference, Apr 2014, Brussels, Belgium. pp.91300W, ⟨10.1117/12.2052156⟩. ⟨hal-01020883⟩