Quantifying single plasmonic nanostructure far-fields with interferometric and polarimetric k-space microscopy

Abstract

Optically resonant nanoantennae are key building blocks for metasurfaces, nanosensors, and nanophotonic light sources due to their ability to control the amplitude, phase, directivity, and polarization of scattered light. Here, we report an experimental technique for the full recovery of all degrees of freedom encoded in the far-field radiated by a single nanostructure using a high-NA Fourier microscope equipped with digital off-axis holography. This method enables full decomposition of antenna-physics in its multipole contributions and gives full access to the orbital and spin angular momentum properties of light scattered by single nano-objects. Our results demonstrate these capabilities through a quantitative assessment of the purity of the “selection rules” for orbital angular momentum transfer by plasmonic spiral nanostructures.

Light-emitting metasurfaces

“…This factor can be corrected for by measurements on trusted references, such as Lambertian emitters, and emitters on air/glass interfaces with highly distinct radiation patterns [131,132]. Also, polarimetric and interferometric back focal plane imaging are possible, but they are potentially hampered by objective birefringence and aberrations [133,134]. Grzela et al [135] demonstrated that the same optical setup can also be used in reverse, i.e.…”

Vortex Beam Generation by Spin-Orbit Interaction with Bloch Surface Waves

“…The uniformity of the polarization orientation is evaluated by extracting the parameter , which provides the local orientation of the polarization ellipse (almost a line, in this case) across the BFP. 45 In Figure 3 m,n both the experimental and the calculated distributions for α( k x , k y ) indicate that the substantially linear polarization follows an axis-symmetric distribution such that the electric field is azimuthally oriented about the beam axis in k x = k y = 0. In this case, the J conservation rule reads as , leading to two fully overlapped beams with SAM σ o = +1 and OAM and σ o = −1 and OAM , respectively (see Figures S6e,f and S7e,f in Supporting Information ).…”

“…The distribution of the parameter , shows a substantially linear polarization corresponding to the doughnut ( ≅ 0) (Figures 3i,l). The uniformity of the polarization orientation is evaluated by extracting the parameter , , which provides the local orientation of the polarization ellipse (almost a line, in this case) across the BFP [40]. In Figures 3m,n When the illumination polarization is switched to LHC ( 1) the input SAM and the grating topological charge possess the same sign.…”

“…In order to evaluate the polarization state of the diffracted light, the polarization ellipse parameter is calculated across the Back Focal Plane (BFP), where S 1 , S 2 , and S 3 are the Stokes parameters. 45 Right-Handed Circular (RHC), Left-Handed Circular (LHC) and Linear Polarizations (LP) correspond to , and ε LP = 0, respectively. Polarization-filtered raw images and Stokes parameter distributions for the structures considered here are shown in the Supporting Information .…”

One-piece polarizing interferometer for ultrafast spectroscopic polarimetry

“…Polarization also has been applied for engineering light–matter interactions in waveguide 8,9 and telecommunication 10 . Recently, nanophotonics has opened a new possibility of ultracompact system based on meta-surfaces with a capability of engineering the polarization of light 11–13 . Spectral interferometry employing polarization technique has been playing a very important role in characterizing optical properties in various fields 14–21 .…”