Dark Mode Excitation in Three-Dimensional Interlaced Metallic Meshes

Area of Science:

• Metamaterials and Nanophotonics
• Electromagnetism and Wave Phenomena

Background:

• Interlaced metallic meshes are 3D metamaterials with unique low-frequency, broadband, nondispersive modes.
• Experimental observation of these modes is challenging due to fabrication complexity and the longitudinal nature of the 'dark mode,' which does not couple to free-space radiation.

Purpose of the Study:

• To achieve the first experimental observation of low-frequency modes in interlaced metallic meshes.
• To demonstrate a method for coupling plane waves to the longitudinal 'dark mode' for characterization.
• To explore the use of these structures for manipulating electromagnetic waves, such as polarization rotation and phase shifting.

Main Methods:

• Fabrication of interlaced metallic meshes using 3D printing.
• Integration of monopole antennas on opposing faces of the mesh structure.
• Measurement of wave propagation and dispersion using coupled antennas.

Main Results:

• Successful experimental observation of low-frequency modes in 3D printed interlaced metallic meshes.
• Demonstration that monopole antennas enable coupling to the longitudinal 'dark mode,' allowing dispersion measurement.
• Achieved polarization rotation and phase shifting of radiation by utilizing orthogonal antennas.

Conclusions:

• The study presents the first experimental validation of low-frequency modes in 3D printed interlaced metallic meshes.
• Antenna integration provides a viable method to excite and probe these previously inaccessible 'dark modes'.
• This work opens avenues for advanced experimental investigations of 3D metamaterials and their applications in wave manipulation.