Sep 9 2022Reviewed by Mila Perera
The so-called generalized Kerker effects allow light to be scattered in a specific direction using all-dielectric nanostructures. However, these effects only exist for a specific polarization or are polarization-independent.
Image Credit: Shutterstock.com/SuperPuay
Polarization-controlled dual lattice Kerker effects in periodic silicon nanorods were proposed and experimentally demonstrated by a research group led by Dr. Guangyuan Li of the Chinese Academy of Sciences’ Shenzhen Institute of Advanced Technology (SIAT).
These findings enable active tuning of the Kerker effects by modifying the incidence polarization or angle, and they can be employed in a variety of applications, such as manipulating the dispersed light’s direction, polarization, and phase, which is critical in nanophotonic chips.
This research was released in the journal Nano Research.
In the duel-lattice Kerkler effects, the incident angles (zero reflection and unitary transmission), or lattice Kerker angles, can be identical or different for the s- and p-polarizations, based on the diameter and height of the silicon nanodisks. By adjusting the lattice periods in both orientations, these lattice Kerker angles can be fine-tuned across a wide range.
Other generalized Kerker effects mentioned in the literature operate primarily under normal incidence and are achieved by altering the geometry parameters. This necessitates exact parameter selection and manufacturing.
By introducing the lattice effect, the so-called lattice Kerker effect can be realized through varying the incident angle. This merit enables active tuning of the Kerker effect in an as-fabricated sample, and thus significantly facilitates the design and fabrication.
Dr. Guangyuan Li, Study Group Lead, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences
When p-polarized light obliquely illuminates the periodic silicon nanodisks, high-order multipoles like electric and magnetic quadrupoles become involved and crucial.
Therefore, the electric dipole surface lattice resonance (ED-SLR) under p-polarization and the magnetic dipole surface lattice resonance (MD-SLR) under s-polarization have different dispersion ratios, resulting in distinct lattice Kerker angles for the s- and p-polarizations.
Journal Reference:
Xiong, L., et al. (2022) Polarization-controlled dual resonant lattice Kerker effects. Nano Research.
Source: https://english.cas.cn/