Tunable/Reconfigurable Metasurfaces: Physics and Applications.

Area of Science:

• Electromagnetism and Materials Science
• Nanotechnology and Optics

Background:

• Metasurfaces are ultrathin metamaterials composed of planar meta-atoms.
• They exhibit tailored electromagnetic (EM) responses, enabling precise control over EM waves.

Purpose of the Study:

• To review recent advancements in tunable and reconfigurable metasurfaces.
• To focus on their working mechanisms, practical applications, and future directions.

Main Methods:

• Categorization of approaches for homogeneous metasurfaces based on external stimuli.
• Summarization of achievements in inhomogeneous metasurfaces with locally tuned meta-atoms.

Main Results:

• Homogeneous metasurfaces provide uniform EM wave manipulation.
• Inhomogeneous metasurfaces allow dynamic control over EM wave-fronts.

Conclusions:

• Active elements enable tunable/reconfigurable metadevices for dynamic EM wave manipulation.
• The field presents ongoing challenges and promising future research avenues.