In-Plane Plasmon Coupling in Topological Insulator Bi$_2$Se$_3$ Thin Films

التفاصيل البيبلوغرافية
العنوان: In-Plane Plasmon Coupling in Topological Insulator Bi$_2$Se$_3$ Thin Films
المؤلفون: Nasir, Saadia, Wang, Zhengtianye, Mambakkam, Sivakumar V., Law, Stephanie
سنة النشر: 2021
المجموعة: Condensed Matter
Physics (Other)
مصطلحات موضوعية: Physics - Optics, Condensed Matter - Materials Science
الوصف: The surface states of the 3D topological insulator (TI), Bi$_2$Se$_3$, are known to host two-dimensional Dirac plasmon polaritons (DPPs) in the terahertz spectral range. In TI thin films, the DPPs excited on the top and bottom surfaces couple, leading to an acoustic and an optical plasmon mode. Vertical coupling in these materials is therefore reasonable well-understood, but in-plane coupling among localized TI DPPs has yet to be investigated. In this paper, we demonstrate in-plane DPP coupling in TI stripe arrays and show that they exhibit dipole-dipole type coupling. The coupling becomes negligible with the lattice constant is greater than approximately 2.8 times the stripe width, which is comparable to results for in-plane coupling of localized plasmons excited on metallic nanoparticles or graphene plasmon polaritons. This understanding could be leveraged for the creation of TI-based metasurfaces.
نوع الوثيقة: Working Paper
DOI: 10.1063/5.0071895
URL الوصول: http://arxiv.org/abs/2109.08515
رقم الأكسشن: edsarx.2109.08515
قاعدة البيانات: arXiv