Polarization-controlled directional scattering for nanoscopic position sensing.
Controlling the propagation and coupling of light to sub-wavelength antennas is a crucial prerequisite for many nanoscale optical devices. Recently, the main focus of attention has been directed towards high-refractive-index materials such as silicon as an integral part of the antenna design. This development is motivated by the rich spectral properties of individual high-refractive-index nanoparticles. Here we take advantage of the interference of their magnetic and electric resonances to achieve strong lateral directionality. For controlled excitation of a spherical silicon nanoantenna, we use tightly focused radially polarized light. The resultant directional emission depends on the antenna's position relative to the focus. This approach finds application as a novel position sensing technique, which might be implemented in modern nanometrology and super-resolution microscopy set-ups. We demonstrate in a proof-of-concept experiment that a lateral resolution in the Ångström regime can be achieved.
Max Planck Institute for the Science of Light, Günther-Scharowsky-St. 1, D-91058 Erlangen, Germany.|Institute of Optics, Information and Photonics, Department of Physics, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 7/B2, D-91058 Erlangen, Germany.
Martin
M
Neugebauer
Max Planck Institute for the Science of Light, Günther-Scharowsky-St. 1, D-91058 Erlangen, Germany.|Institute of Optics, Information and Photonics, Department of Physics, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 7/B2, D-91058 Erlangen, Germany.
Paweł
P
Woźniak
Max Planck Institute for the Science of Light, Günther-Scharowsky-St. 1, D-91058 Erlangen, Germany.|Institute of Optics, Information and Photonics, Department of Physics, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 7/B2, D-91058 Erlangen, Germany.
Ankan
http://orcid.org/0000-0002-2029-825X
A
Bag
Max Planck Institute for the Science of Light, Günther-Scharowsky-St. 1, D-91058 Erlangen, Germany.|Institute of Optics, Information and Photonics, Department of Physics, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 7/B2, D-91058 Erlangen, Germany.|Department of Physics, University of Ottawa, 25 Templeton Street, Ottawa, Ontario K1N 6N5, Canada.
Gerd
G
Leuchs
Max Planck Institute for the Science of Light, Günther-Scharowsky-St. 1, D-91058 Erlangen, Germany.|Institute of Optics, Information and Photonics, Department of Physics, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 7/B2, D-91058 Erlangen, Germany.|Department of Physics, University of Ottawa, 25 Templeton Street, Ottawa, Ontario K1N 6N5, Canada.
Peter
P
Banzer