Optical spectra of 2D monolayers from time-dependent density functional theory

Abstract

The optical spectra of two-dimensional (2D) periodic systems provide a challenge for time-dependent density-functional theory (TDDFT) because of the large excitonic effects in these materials. In this work we explore how accurately these spectra can be described within a pure Kohn-Sham time-dependent density-functional framework, i.e., a framework in which no theory beyond Kohn-Sham density-functional theory, such as $GW$, is required to correct the Kohn-Sham gap. To achieve this goal we adapted a recent approach we developed for the optical spectra of 3D systems [Cavo, Berger, Romaniello, Phys. Rev. B 101, 115109 (2020)] to those of 2D systems. Our approach relies on the link between the exchange-correlation kernel of TDDFT and the derivative discontinuity of ground-state density-functional theory, which guarantees a correct quasi-particle gap, and on a generalization of the polarization functional [Berger, Phys. Rev. Lett., 115, 137402 (2015)], which describes the excitonic effects. We applied our approach to two prototypical 2D monolayers, $h$-BN and MoS${}_2$. We find that our protocol gives a qualitative good description of the optical spectrum of $h$-BN, whereas improvements are needed for MoS${}_2$ to describe the intensity of the excitonic peaks.

arXiv comment11 pages, 4 figures

References in corpus (35)

• Atomically thin MoS2: A new direct-gap semiconductor
• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• The GW method
• Optical Spectrum of MoS${}_2$: Many-body Effects and Diversity of Exciton States
• Hexagonal boron nitride is an indirect bandgap semiconductor
• Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
• The Computational 2D Materials Database: High-Throughput Modeling and Discovery of Atomically Thin Crystals
• Computational 2D Materials Database: Electronic Structure of Transition-Metal Dichalcogenides and Oxides
• Dielectric screening in two-dimensional insulators: Implications for excitonic and impurity states in graphane
• Effect of spin-orbit interaction on the excitonic effects in single-layer, double-layer, and bulk MoS2
• Direct imaging of the band profile in single layer $Mo{S}_2$ on graphite: quasiparticle energy gap, metallic edge states and edge band bending
• Probing excitonic states in ultraclean suspended two-dimensional semiconductors by photocurrent spectroscopy
• The GW compendium: A practical guide to theoretical photoemission spectroscopy
• Huge excitonic effects in layered hexagonal boron nitride
• Screening and Many-Body Effects in Two-Dimensional Crystals: Monolayer MoS${}_2$
• Excitons in boron nitride nanotubes: dimensionality effects
• Kohn-Sham potential with discontinuity for band gap materials
• How dielectric screening in two-dimensional crystals affects the convergence of excited-state calculations: Monolayer MoS${}_2$
• Quasiparticle GW calculations for solids, molecules and 2D materials
• Precise and reversible band gap tuning in single-layer MoSe2 by uniaxial strain
• Bootstrap approximation for the exchange-correlation kernel of time-dependent density functional theory
• Nonempirical Range-separated Hybrid Functionals for Solids and Molecules
• Broad Band Optical Properties of Large Area Monolayer CVD Molybdenum Disulfide
• Mapping from current densities to vector potentials in time-dependent current-density functional theory
• Excitons in boron nitride single layer
• Comparative study of hybrid functionals applied to structural and electronic properties of semiconductors and insulators
• Direct and indirect excitons in boron nitride polymorphs: a story of atomic configuration and electronic correlation
• Excitons in hexagonal boron nitride single-layer: a new platform for polaritonics in the ultraviolet
• Optical spectra of solids obtained by time-dependent density-functional theory with the jellium-with-gap model exchange-correlation kernel
• Estimating Excitonic Effects in the Absorption Spectra of Solids: Problems and Insight from a Guided Iteration Scheme
• Fully parameter-free calculation of optical spectra for insulators, semiconductors and metals from a simple polarization functional
• Dimensionality of excitons in stacked van der Waals materials: The example of hexagonal boron nitride
• Optical properties of periodic systems within the current-current response framework: pitfalls and remedies
• Accurate optical spectra of solids from pure time-dependent density-functional theory

Cited by in corpus (7)

• Absorption and optical selection rules of tunable excitons in biased bilayer graphene
• Two limit cases of twisted hBN bilayers and their excitonic response
• Including many-body effects into the Wannier-interpolated quadratic photoresponse tensor
• Anisotropic linear and non-linear excitonic optical properties of buckled monolayer semiconductors
• Excitonic effects in time-dependent density functional theory from zeros of the density response
• Tunable nonlinear excitonic optical response in biased bilayer graphene
• Bandgap of two-dimensional materials: Thorough assessment of modern exchange-correlation functionals