Analytic model of energy spectrum and absorption spectra of bilayer graphene

2012 ◽  
Vol 111 (10) ◽  
pp. 103714 ◽  
Author(s):  
C. P. Chang
Keyword(s):  
Energy Spectrum ◽  
Absorption Spectra ◽  
Bilayer Graphene ◽  
Analytic Model

An analytical approach for the energy spectrum and optical properties of gated bilayer graphene

RSC Advances ◽  
2014 ◽  
Vol 4 (61) ◽  
pp. 32117-32126 ◽  
Author(s):  
Cheng-Peng Chang
Keyword(s):  
Optical Properties ◽  
Energy Spectrum ◽  
Matrix Element ◽  
Absorption Spectra ◽  
Analytical Approach ◽  
Bilayer Graphene ◽  
Wave Functions ◽  
Dipole Matrix Element ◽  
Exact Energy

An analytical approach is developed to access the exact energy spectrum, wave functions, dipole matrix element (Mfi) and absorption spectra (A(ω)) of gated Bernal bilayer graphene.

scholarly journals Properties of Bilayer Graphene Quantum Dots for Integrated Optics: An Ab Initio Study

Photonics ◽  
2020 ◽  
Vol 7 (3) ◽  
pp. 78
Author(s):  
Majid Ghandchi ◽  
Ghafar Darvish ◽  
Mohammad Kazem Moravvej-Farshi
Keyword(s):  
Quantum Dots ◽  
Absorption Spectra ◽  
Integrated Optics ◽  
Light Absorption ◽  
Near Infrared ◽  
Graphene Quantum Dots ◽  
Bilayer Graphene ◽  
Infrared Range ◽  
Out Of Plane ◽  
Near Infrared Range

Due to their bandgap engineering capabilities for optoelectronics applications, the study of nano-graphene has been a topic of interest to researchers in recent years. Using a first-principles study based on density functional theory (DFT) and thermal DFT, we investigated the electronic structures and optical properties of bilayer graphene quantum dots (GQDs). The dielectric tensors, absorption spectra, and the refractive indexes of the bilayer GQDs were obtained for both in-plane and out-of-plane polarization. In addition, we calculated the absorption spectra via time-dependent DFT (TD-DFT) in the linear response regime. The TDDFT results show that a blue shift occurs in the absorption spectrum, which is consistent with the experimental results. In this investigation, we consider triangular and hexagonal GQDs of various sizes with zigzag and armchair edges. Our simulations show that unlike monolayer GQDs, for which light absorption for out-of-plane polarization occurs in the ultraviolet wavelength range of 85–250 nm, the out-of-plane polarization light absorption peaks in the bilayer GQDs appear in the near-infrared range of 500–1600 nm, similar to those in bilayer graphene sheets. The out-of-plane polarization light absorption peaks in the near-infrared range make bilayer GQDs suitable for integrated optics and optical communication applications.

scholarly journals Landau levels for graphene layers in noncommutative plane

2021 ◽  
pp. 2150087
Author(s):  
Lucas Sourrouille
Keyword(s):  
Energy Spectrum ◽  
Bilayer Graphene ◽  
Landau Levels ◽  
Graphene Layers ◽  
Zero Modes ◽  
Commutative Space ◽  
Noncommutative Plane

Starting from the zero modes of the single and bilayer graphene Hamiltonians we develop a mechanism to construct the eigenstates and eigenenergies for Landau levels in noncommutative plane. General formulas for the spectrum of energies are deduced, for both cases, single and bilayer graphene. In both cases we find that the effect to introduce noncommutative coordinates is a shift in the energy spectrum with respect to result obtained in commutative space.

Sign in / Sign up

Export Citation Format

Share Document