Excitonic effects in the optical properties of 2D materials: An equation of motion approach

Abstract

We present a unified description of the excitonic properties of four monolayer transition-metal dichalcogenides (TMDC's) using an equation of motion method for deriving the Bethe-Salpeter equation in momentum space. Our method is able to cope with both continuous and tight-binding Hamiltonians, and is less computational demanding than the traditional first-principles approach. We show that the role of the exchange energy is essential to obtain a good description of the binding energy of the excitons. The exchange energy at the $\Gamma -$point is also essential to obtain the correct position of the C-exciton peak. Using our model we obtain a good agreement between the Rydberg series measured for WS${}_2$. We discuss how the absorption and the Rydberg series depend on the doping. Choosing $r_0$ and the doping we obtain a good qualitative agreement between the experimental absorption and our calculations for WS${}_2$. We also derive a semi-analytical version of Ellitot's formula for TMDC's.

Accepted for publication in 2D Materials

References in corpus (18)

• Electric Field Effect in Atomically Thin Carbon Films
• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
• Exciton Binding Energy of Monolayer WS2
• Determination of band alignment in the single layer MoS2/WSe2 heterojunction
• Mono- and Bilayer WS2 Light-Emitting Transistors
• Probing excitonic states in ultraclean suspended two-dimensional semiconductors by photocurrent spectroscopy
• Exciton band structure of monolayer MoS2
• Measurement of high exciton binding energy in the monolayer transition-metal dichalcogenides WS2 and WSe2
• Optical properties of atomically thin transition metal dichalcogenides: Observations and puzzles
• Excitons in anisotropic 2D semiconducting crystals
• Probing the spin-polarized electronic band structure in monolayer transition metal dichalcogenides by optical spectroscopy
• Optical properties of correlated materials -- Generalized Peierls approach and its application to VO2
• Density dependent exchange contribution to $\partial \mu /\partial n$ in extrinsic graphene
• Excitonic effects in the optical conductivity of gated graphene
• Exciton complexes in low dimensional transition metal dichalcogenides
• Dynamical gap generation in graphene nanoribbons: An effective relativistic field theoretical model

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