A dynamically tunable chiral mirror enabled by electrochromic metasurfaces operating at telecommunication wavelengths

Zanotto S, Buchheit A, Muñoz-Castro M, Wiemhöfer H, Morichetti F, Melloni A

Abstract

In this paper we introduce the concept of tunable chiral mirror and provide an experimental evidence of its implementation. A chiral mirror, i.e., a device which reflects circularly polarized light of a single handedness without inverting it, has been synthesized by numerical optimization of a metasurface composed of non-centrosymmetric meta-atoms. Operation has been targeted to the telecommunication wavelength through a judicious rescaling and reshaping of the meta-atom geometry. Embedding an electrochromic material (V2O5) in the layer stack, dynamical reconfiguration of the chiral mirror has been achieved, with a theoretical modulation depth of more than 35 dB. Reconfiguration is self-holding and reversible, showing that electrochromism in V2O5 could prove to be a powerful tool to modulate the response of complex beam shaping and polarization handling metasurface-based ultrathin photonic components.