Generating multiple vortex beams simultaneously and independently in different directions by elaborately splicing...

Area of Science:

• Optics and Photonics
• Metamaterials
• Electromagnetics

Background:

• Generating multiple, independent vortex beams simultaneously is crucial for advanced optical systems.
• Traditional methods often face challenges in controlling individual beam properties and preventing interference.

Purpose of the Study:

• To demonstrate a novel method for simultaneously generating multiple linear polarized (LP) vortex beams in different directions.
• To achieve independent control over each generated vortex beam with minimal cross-talk and diffraction.

Main Methods:

• Elaborately splicing multiple transmissive metasurfaces (MSs) with polarization isolation characteristics.
• Optimizing the array radius and metasurface-to-array distance for precise beam deflection.
• Utilizing antenna arrays to illuminate individual MSs, ensuring selective beam generation.

Main Results:

• Successfully generated multiple LP vortex beams with distinct orbital angular momentum (OAM) modes simultaneously and independently.
• Achieved well-performed deflection vortex beams with low side-lobe levels and minimal diffraction.
• Demonstrated effective polarization isolation between adjacent MSs, suppressing cross-polarization.

Conclusions:

• The proposed method of splicing transmissive metasurfaces is effective for simultaneous, independent generation of multiple LP vortex beams.
• The technique offers precise control over OAM modes and beam directionality, verified by simulations and measurements.