High_Quality Tunable Graphene Plasmonic Metamaterials
Abstract
Plasmonic metamaterials have been proposed as a platform for engineering materialsÕ optical properties such as permittivity e , permeability µ , and refractive index n . Graphene recently emerged as a promising new candidate for plasmonics and metamaterials due to its broadband light-matter interaction, Fermi-level tunability, and ultrahigh carrier mobility that could lead to both applications based on broadband, low-loss, and tunable active metamaterials and fundamental studies on nonreciprocal plasmons, nonlinear optics, and quantum Cerenkov effect, to name a few examples. However, the experimental realization of this potential is currently held back by the limited quality of prepared graphene samples that strongly restricts device performance in terms of dissipative loss and working wavelength. In this project, we propose a device implementation concept that addresses these concerns. By using hexagonal boron nitride (hBN-) encapsulated CVD graphene samples and applying nanoscale electrolytic gating of graphene to avoid direct graphene patterning processes that typically introduce impurities and defects, we aim to maintain the high carrier mobility of graphene as much as possible. This approach would allow us to answer the question of whether high quality factor graphene plasmons are experimentally achievable and whether graphene plasmonic metamaterials can live up to their potential. The likely successful demonstration of improved graphene plasmonic modes will then lead to experimental exploration of the quasi-relativistic Doppler effect and graphene metamaterial-based flat optics, which are the other two main research tasks in this project. Finally, as a side effort, we aim to enhance grapheneÕs optical nonlinearity by extreme mode-confinement of plasmonic mode in a graphene nanodisk. Nanoantenna-assisted coupling between freespace optical mode and graphene plasmonic mode will be numerically simulated to provide insight for future experimental studies.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 11, 2018
- Source ID
- W911NF1710435
Entities
People
- Dirk Englund
Organizations
- Army Contracting Command
- Massachusetts Institute of Technology
- United States Army