1 research outputs found
Quantitative 3D Phase Imaging of Plasmonic Metasurfaces
Coherence-controlled
holographic microscopy (CCHM) is a real-time,
wide-field, and quantitative light-microscopy technique enabling 3D
imaging of electromagnetic fields, providing complete information
about both their intensity and phase. These attributes make CCHM a
promising candidate for performance assessment of phase-altering metasurfaces,
a new class of artificial materials that allow to manipulate the wavefront
of passing light and thus provide unprecedented functionalities in
optics and nanophotonics. In this paper, we report on our investigation
of phase imaging of plasmonic metasurfaces using holographic microscopy.
We demonstrate its ability to obtain phase information from the whole
field of view in a single measurement on a prototypical sample consisting
of silver nanodisc arrays. The experimental data were validated using
FDTD simulations and a theoretical model that relates the obtained
phase image to the optical response of metasurface building blocks.
Finally, in order to reveal the full potential of CCHM, we employed
it in the analysis of a simple metasurface represented by a plasmonic
zone plate. By scanning the sample along the optical axis we were
able to create a quantitative 3D phase map of fields transmitted through
the zone plate. The presented results prove that CCHM is inherently
suited to the task of metasurface characterization. Moreover, as the
temporal resolution is limited only by the camera framerate, it can
be even applied in analysis of actively tunable metasurfaces