Long-lived domain wall plasmons in gapped bilayer graphene

Topological domain walls in dual-gated gapped bilayer graphene host edge states that are gate-tunable and valley polarized. Here we predict that plasmonic collective modes can propagate along these topological domain walls even at zero bulk density and possess a markedly different character from tha...

Full description

Saved in:
Bibliographic Details
Main Authors: Hasdeo, Eddwi H., Song, Justin Chien Wen
Other Authors: School of Physical and Mathematical Sciences
Format: Article
Language:English
Published: 2019
Subjects:
Online Access:https://hdl.handle.net/10356/105435
http://hdl.handle.net/10220/48666
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Nanyang Technological University
Language: English
Description
Summary:Topological domain walls in dual-gated gapped bilayer graphene host edge states that are gate-tunable and valley polarized. Here we predict that plasmonic collective modes can propagate along these topological domain walls even at zero bulk density and possess a markedly different character from that of bulk plasmons. Strikingly, domain wall plasmons are extremely long-lived with plasmon lifetimes that can be orders of magnitude larger than the transport scattering time in the bulk at low temperatures. Importantly, long domain wall plasmon lifetimes persist even at room temperature with values up to a few picoseconds. Domain wall plasmons possess a rich phenomenology including plasmon oscillation over a wide range of frequencies (up to the mid-infrared), tunable subwavelength electromagnetic confinement lengths, as well as a valley polarization for forward/backward propagating modes. Its unusual features render them as a new tool for realizing low-dissipation plasmonics that transcend the restrictions of the bulk.