Non-invasive control of excitons in two-dimensional materials

Abstract

We investigate how external screening shapes excitons in two-dimensional (2d) semiconductors embedded in laterally structured dielectric environments. An atomic scale view of these elementary excitations is developed using models which apply to a variety of materials including transition metal dichalcogenides (TMDCs). We find that structured dielectrics imprint a peculiar potential energy landscape on excitons in these systems: While the ground-state exciton is least influenced, higher excitations are attracted towards regions with high dielectric constant of the environment. This landscape is "inverted" in the sense that low energy excitons are less strongly affected than their higher energy counterparts. Corresponding energy variations emerge on length scales of the order of a few unit cells. This opens the prospect of trapping and guiding of higher excitons by means of tailor-made dielectric substrates on ultimately small spatial scales.

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Cited by in corpus (12)

• The dielectric impact of layer distances on exciton and trion binding energies in van der Waals heterostructures
• Engineering of Neutral Excitons and Exciton Complexes in Transition Metal Dichalcogenide Monolayers through External Dielectric Screening
• Prospects and limitations of transition-metal dichalcogenide laser gain materials
• Moiré-Bose-Hubbard model for interlayer excitons in twisted transition metal dichalcogenide heterostructures
• Excitation-induced transition to indirect band gaps in atomically thin transition metal dichalcogenide semiconductors
• Excitons in Bulk and Layered Chromium Tri-Halides: From Frenkel to the Wannier-Mott Limit
• Dark-exciton driven energy funneling into dielectric inhomogeneities in two-dimensional semiconductors
• Frequency-dependent substrate screening of excitons in atomically thin transition metal dichalcogenide semiconductors
• Dynamical screening effects of substrate phonons on two-dimensional excitons
• Electronic Properties of Defective MoS${}_2$ Monolayers Subject to Mechanical Deformations: A First-Principles Approach
• Entropy and Temperature in finite isolated quantum systems
• Controlling magnetic frustration in 1T-TaS${}_2$ via Coulomb engineered long-range interactions