Optical activity and transport in twisted bilayer graphene: the essence of spatial dispersion effects

التفاصيل البيبلوغرافية
العنوان: Optical activity and transport in twisted bilayer graphene: the essence of spatial dispersion effects
المؤلفون: Ho, S. Ta, Do, V. Nam
سنة النشر: 2023
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Mesoscale and Nanoscale Physics
الوصف: This study investigates optical activity and quantum transport in twisted bilayer graphene (TBG) systems, demonstrating that the former results from spatial dispersion effects. The transfer matrix method is used to solve the propagation of electromagnetic waves through two graphene layers that act as the coupling surfaces of a dielectric slab. The resulting optical conductivity tensor is decomposed into a local and a drag part, with the drag transverse conductivity $\sigma_{xy}^{(drag)}$ governing the TBG system's optical property. An effective continuum model is employed to analyze electron state formation and calculate relevant parts of the optical conductivity tensor. Correlation of electron motions leads to incomplete cancellation and a finite $\sigma_{xy}^{(drag)}$ in the chiral TBG lattice. The study also calculates DC conductivity, showing TBG supports quantum conductivity proportional to $e^2/h$ at the intrinsic Fermi energy.
Comment: arXiv admin note: substantial text overlap with arXiv:2205.12675
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevB.107.195141
الوصول الحر: http://arxiv.org/abs/2303.07330Test
رقم الانضمام: edsarx.2303.07330
قاعدة البيانات: arXiv