Liquid switchable radial polarization converters made of sculptured thin films

IBERTRIVA 2019 X Iberian Conference on Tribology – IBERTRIB, XI Iberian Vacuum Conference - RIVA, Seville, Spain,June 26-28Peer reviewe

Liquid switchable radial polarization converters made of sculptured thin films

7 pags., 6 figs., 1 app.A radial polarization converter is a super-structured optical retarder that converts a conventional linearly polarized light beam into a structured beam with radial or azimuthal polarization. We present a new type of these sophisticated optical elements, which is made of porous nanostructured sculptured single thin films or multilayers prepared by physical vapor deposition at an oblique angle. They are bestowed with an axisymmetric retardation activity (with the fast axis in a radial configuration). In particular, a Bragg microcavity multilayer that exhibits a tunable transmission peak in the visible range with a retardance of up to 0.35 rad has been fabricated using this methodology. Owing to the highly porous structure of this type of thin films and multilayers, their retardance could be switched off by liquid infiltration. These results prove the possibility of developing wavelength dependent (through multilayer optical design) and switchable (through vapor condensation or liquid infiltration within the pore structure) radial polarization converters by means of oblique angle physical vapor deposition.We acknowledge the support of the European Regional Development Funds program (EU-FEDER), the Spanish MinistryEconomy, Industry, and Competitiveness (projects 201560E055,MAT2016-79866-R, RECUPERA 2020 and Red CONSOLIDER MAT2015-69035-REDC)