Generating diverse functionalities simultaneously and independently for arbitrary linear polarized illumination...

Area of Science:

• Electromagnetics
• Metamaterials
• Nanophotonics

Background:

• Multifunctional metasurfaces offer integrated wave manipulation but are limited by polarization states and concurrent function realization.
• Existing designs struggle to perform diverse functions simultaneously, hindering practical applications of metadevices.

Purpose of the Study:

• To propose a novel chiral transmission-reflection-selective bifunctional metasurface strategy.
• To enable independent control over electromagnetic waves for distinct functions in reflection and transmission channels.
• To achieve concurrent operation under arbitrary linear polarized incident waves.

Main Methods:

• Utilizing rotation-induced geometric phase modulation for co-polarized reflection channel with left-handed circular polarized (LCP) incidence.
• Employing scaling-induced propagation phase modulation for co-polarized transmission channel with right-handed circular polarized (RCP) incidence.
• Designing and fabricating proof-of-concept metadevices, including an orbital angular momentum (OAM) generator and a bifocal metalens.

Main Results:

• Demonstrated concurrent generation of two independent functions in reflection and transmission channels.
• Validated the metasurface's performance for both LCP and RCP incidence, as well as arbitrary linear polarized (LP) waves.
• Experimental and simulation results showed good agreement with theoretical predictions for the designed metadevices.

Conclusions:

• The proposed chiral bifunctional metasurface strategy successfully enables simultaneous, independent functions.
• This design significantly advances the development of multifunctional metadevices for diverse engineering applications.
• The approach opens new avenues for integrated and versatile electromagnetic wave manipulation.