Coupling plasmon-waveguide resonance and multiple plasma modes in hyperbolic metamaterials for high-performance...

Area of Science:

• Plasmonics and Nanophotonics
• Metamaterials
• Biosensing Technologies

Background:

• Plasmon-waveguide resonance (PWR) sensors offer narrow linewidths for label-free sensing.
• Low surface electric field intensity in conventional PWR sensors limits biomolecule detection sensitivity.
• Hyperbolic metamaterials (HMMs) offer potential for electric field enhancement.

Purpose of the Study:

• To investigate the coupling of PWR with multiple plasma modes in an HMM for enhanced sensing.
• To combine the narrow linewidth of PWR with the electric field enhancement of HMMs.
• To improve the detection ability of biomolecules in plasmon-based sensors.

Main Methods:

• Fabrication of a PWR-HMM sensor comprising a gold film, dielectric layer, and multilayer HMM (Au/Al2O3).
• Excitation of multiple plasma modes in the HMM using the evanescent field of PWR.
• Characterization of sensor performance, including figure of merit (FOM) and bulk/surface sensitivity.

Main Results:

• The PWR-HMM sensor achieved a figure of merit of 5417/RIU, 11.7 times higher than conventional gold film sensors.
• Maximum bulk sensitivity reached 43,000 nm/RIU.
• Surface electric field intensity and surface sensitivity increased by four and two times, respectively, compared to PWR sensors.
• PWR-HMM sensors demonstrated 20% higher surface sensitivity than PWR-nanoparticle sensors.

Conclusions:

• Coupling PWR with multiple plasma modes in HMMs significantly enhances sensor performance.
• The developed PWR-HMM sensor offers superior sensitivity and electric field intensity for biosensing.
• This approach holds promise for addressing critical challenges in biological, medical, and clinical applications.