Recently, Professor Li Tao and Academician Zhu Shining, along with their research team from the School of Engineering and Applied Sciences, published a research paper titled “Metasurface-Enabled On-Chip Manipulation of Higher-Order Poincaré Sphere Beams”, on Nano Letters (ACS Publications21/acs.nanolett.3c00021).
The abstract of the paper is as following:
An integrated way to generate and manipulate higher-order Poincaré sphere beams (HOPBs) is a sought-after goal in photonic integrated circuits for high-capacity communication systems. Here, the research team demonstrates a novel method for on-chip generation and manipulation of HOPBs through combining metasurface with optical waveguides on lithium niobate on insulator platform. With phase modulation by a diatomic geometric metasurface, guided waves are extracted into free space with a high signal-to-noise ratio in the form of two orthogonal circularly polarized optical vortices which are linearly superposed into HOPBs. Meanwhile, a dual-port waveguide crossing is established to reconfigure the output states into an arbitrary point on a higher-order Poincaré sphere based on in-plane interference of two guided waves. The work’s approach provides a promising solution to generate and manipulate the HOPBs in a compact manner, which would be further enhanced by employing the electro-optical modulation on a lithium niobate waveguide to access a fully tunable scheme.
1. Schematic diagram of integrated superconfiguration surface modulated panglais beam.
2. On-chip generation of a Pongare beam. (a-c) Superconfiguration of the surface-integrated lithium niobate optical waveguide structure, (d-e) generated column-vector polarized beam.
3. (a-e) Modulation of the relative intensity of the guided modes corresponding to the evolution of the beam state of Panglais.
4. (a-e) The evolution of the state of the Panglais beam corresponding to the phase difference of the modulated guide mode.
Translator: Shao Yihang
Editors: Guo Ankang, Shao Yihang
