Abstract: The optical device can comprise a substrate having a first face opposite a second face, a thickness between the first face and the second face, the first face and the second face being planar, the first face being parallel the second face, the substrate being transparent to an electromagnetic radiation in a given spectrum; a planar polarization-dichroic focusing lens covering the first face, the lens having a first focusing power for a first polarization of the electromagnetic radiation and a second focusing power for a second polarization of the electromagnetic radiation, the second focusing power being different from the first focusing power; and a planar polarization-dichroic mirror covering the second face, the mirror being reflective to the first polarization and transparent to the second polarization.

Abstract: The gel made of graphene oxide co-doped with boron nitrogen can be functionalized with a receptor, can be passivated by a passivation agent, and can have particular expressions of bonds to favor charge carrier mobility. The gel can be used in the context of a sensor via the interaction between the receptor and an analyte to be detected.