Quasi-3D Plasmonic Metamaterials with Highly Stretch-Tunable Optical Responses

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Three-dimensional (3D) metal nanoparticle (NP) assemblies are crucial for optoelectronics and sensing.
• Achieving uniform, sub-10 nm interparticle spacing in tunable media for plasmonic metamaterials is challenging.

Purpose of the Study:

• To create mechanically reconfigurable plasmonic nanocomposites with tunable optical properties.
• To investigate the strain-induced modulation of plasmonic coupling in 3D nanoparticle architectures.

Main Methods:

• Fabrication of gallium nanoparticle (GaNP)/polydimethylsiloxane (PDMS) nanocomposites via single-step Ga evaporation.
• Characterization of multilayered NP architectures and interparticle spacing.
• Application of biaxial strain to induce spectral shifts and FDTD simulations to analyze plasmonic coupling.

Main Results:

• The GaNP/PDMS nanocomposites formed quasi-3D plasmonic metamaterials with narrow interparticle spacing.
• Collective plasmon resonances hybridized with cavity modes, forming plasmon-polariton states.
• Biaxial strain induced a reversible spectral shift exceeding 300 nm due to modulated intra- and interlayer plasmonic coupling.

Conclusions:

• The study presents a novel method for creating mechanically tunable plasmonic metamaterials.
• Understanding nanoparticle-polymer interactions is advanced.
• These findings support the development of advanced, strain-tunable optoelectronic and sensing devices.