Multipolar and dark-mode plasmon resonances on drilled silver nano-triangles

Area of Science:

• Plasmonics
• Nanophotonics
• Optical Metamaterials

Background:

• Dark-mode plasmon resonances are typically difficult to excite.
• Nanostructures and nano-antennas are crucial components in controlling light at the nanoscale.

Purpose of the Study:

• To investigate a novel method for exciting dark-mode plasmon resonances.
• To explore the use of nano-antennas coupled to nanostructures for enhanced light manipulation.

Main Methods:

• Numerical simulations were employed to model the plasmonic behavior.
• A prototypical nanostructure (drilled silver nanotriangle) and a variable aspect ratio nano-antenna were utilized.
• The system was analyzed under plane wave and electron beam irradiation.

Main Results:

• A baseline understanding of the drilled nanotriangle's response was established.
• The addition of a nano-antenna successfully stimulated additional dark-mode plasmon resonances.
• The coupled system demonstrated a rich variety of radiant and sub-radiant resonance modes.

Conclusions:

• A nano-antenna coupled to a nanostructure provides a general and effective method for exciting dark-mode plasmon resonances with plane wave light.
• This approach offers precise control over light-matter interactions at the nanoscale.
• The findings pave the way for advanced applications in nanophotonics and metamaterials.