Babinet-bilayered geometric phase optical elements

Etienne Brasselet (1)

1 LOMA - Laboratoire Ondes et Matière d'Aquitaine

Geometric phase optical elements based on structured anisotropy are widely used for phase shaping via their orienta-tional degree of freedom. To date, amplitude shaping via space-variant retardance is much less investigated, a practical reason being that the spin-orbit interaction of light couples retardance with the dynamic part of the optical phase. Inspired by the complementary diffractive elements associated with Babinet's principle, a bilayered subwavelength grating design is proposed in order to cancel out the spatial modulation of the dynamic phase usually associated with space-variant birefringent phase retardation. This concept is illustrated in the framework of single-mode Laguerre Gauss –beam shaping.

Mots clés: Laser beam shaping; Subwave length structures

Domaines: Optique [physics.optics]

Etienne Brasselet. Babinet-bilayered geometric phase optical elements. Optics Letters, 2018, 43 (11), pp.2623-2626. ⟨10.1364/OL.43.002623⟩. ⟨hal-01802762⟩