Long-Lived Domain Wall Plasmons in Gapped Bilayer Graphene

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanoscience

Background:

• Topological domain walls in dual-gated gapped bilayer graphene support tunable, valley-polarized edge states.
• Bulk plasmons in graphene are limited by short lifetimes and dissipation.

Purpose of the Study:

• To predict and characterize novel plasmonic collective modes propagating along topological domain walls in gapped bilayer graphene.
• To investigate the unique properties and potential applications of these domain wall plasmons.

Main Methods:

• Theoretical prediction and modeling of plasmonic collective modes.
• Analysis of domain wall plasmon properties including lifetime, frequency range, and confinement.
• Comparison with bulk plasmon characteristics.

Main Results:

• Domain wall plasmons predicted to propagate along topological domain walls at zero bulk density.
• These plasmons exhibit significantly longer lifetimes than bulk plasmons, persisting up to room temperature (picosecond scale).
• Domain wall plasmons show tunable confinement, mid-infrared frequency range, and valley polarization.

Conclusions:

• Domain wall plasmons represent a new class of low-dissipation plasmonic modes.
• Their unique features overcome limitations of bulk plasmons, enabling new plasmonic device possibilities.
• This discovery opens avenues for advanced, efficient plasmonic applications in graphene systems.