Independent bidirectional wavefront multiplexing based on dual-band multi-polarization full-space metasurfaces

Area of Science:

• Electromagnetic Metasurfaces
• Wavefront Engineering
• Metaphotonic Devices

Background:

• Conventional metasurfaces are limited to single domains (reflection or transmission).
• Integrating frequency, polarization, and spatial multiplexing in metasurfaces is challenging.
• Full-space manipulation requires advanced bidirectional control.

Purpose of the Study:

• To develop a passive dual-band, multi-polarization (DBMP) full-space metasurface.
• To achieve independent wavefront control across different frequency and polarization states.
• To overcome limitations of conventional half-space metasurface operations.

Main Methods:

• Utilized a symmetry-broken tri-layer architecture for metasurface design.
• Enabled manipulation of dual-linearly polarized waves (lower band) and dual-circularly polarized waves (higher band).
• Integrated simultaneous transmission and reflection modes within a compact platform.

Main Results:

• Demonstrated independent full-space wavefront control for distinct wave properties.
• Achieved high operational efficiency and robust angular stability under oblique incidence.
• Verified high-fidelity generation of four independent, highly directive beams through experimental characterization and numerical simulations.
• Observed negligible interband crosstalk between operational bands.

Conclusions:

• The developed DBMP metasurface offers a versatile platform for multi-dimensional electromagnetic integration.
• The design can be scaled to terahertz and optical frequencies for compact metaphotonic devices.
• This work advances the capabilities of full-space metasurfaces for complex wavefront manipulation.