Triangular lattice exciton model

Abstract

We present a minimalistic equilateral triangular lattice model, from which we derive electron and exciton band structures for semiconducting transition-metal dichalcogenides. With explicit consideration of the exchange interaction, this model is appropriate across the spectrum from Wannier to Frenkel excitons. The single-particle contributions are obtained from a nearest-neighbor tight-binding model parameterized using the effective mass and spin-orbit coupling. The solutions to the characteristic equation, computed in direct space, are in qualitative agreement with first-principles calculations and highlight the inadequacy of the two-dimensional hydrogen model to describe the lowest-energy exciton bands. The model confirms the lack of subshell degeneracy and shows that the A-B exciton split depends on the electrostatic environment as well as the spin-orbit interaction.

6 pages, 5 figures

References in corpus (21)

• Two Dimensional Atomic Crystals
• Synthesis of Large-Area MoS2 Atomic Layers with Chemical Vapor Deposition
• Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Optical Spectrum of MoS${}_2$: Many-body Effects and Diversity of Exciton States
• Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
• Tightly bound excitons in monolayer WSe2
• Valley Dependent Optoelectronics from Inversion Symmetry Breaking
• Probing Excitonic Dark States in Single-layer Tungsten Disulfide
• Quasiparticle band structures and optical properties of strained monolayer MoS2 and WS2
• Breaking of valley degeneracy by magnetic field in monolayer MoSe2
• Exciton Binding Energy of Monolayer WS2
• Valley Splitting and Polarization by the Zeeman Effect in Monolayer MoSe2
• 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
• Exciton fine structure and spin decoherence in monolayers of transition metal dichalcogenides
• Analytical approach to excitonic properties of MoS2
• Efficient $\mathcal{O}(N^2)$ approach to solve the Bethe-Salpeter equation for excitonic bound states
• Temperature Renormalization of Optical Spectra of Monolayer MoS2
• New Mechanism for Strongly Bound Excitons in Gapless Two-Dimensional Structures

Cited by in corpus (5)

• Theory of Exciton-Phonon Coupling
• Excitons in boron nitride single layer
• Probing Many-Body Interactions in Monolayer Transition-Metal Dichalcogenides
• Hybrid k$\cdot$p tight-binding model for subbands and infrared intersubband optics in few-layer films of transition-metal dichalcogenides: MoS${}_2$, MoSe${}_2$, WS${}_2$ and WSe${}_2$
• Exact solution of an exciton energy for a monolayer medium