Acoustically Driven Stark Effect in Transition Metal Dichalcogenide Monolayers

Author(s)

Scolfaro, Diego ^[1] ; Finamor, Matheus ^[1] ; Trinchao, Luca O. ^[1] ; Rosa, Barbara L. T. ^[2] ; Chaves, Andrey ^{[3, 4]} ; Santos, V, Paulo ; Iikawa, Fernando ^[1] ; Couto, Jr., Odilon D. D. ^[1]

Affiliation

^[1] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083859 Campinas - Brazil

^[2] Univ Fed Minas Gerais UFMG, Dept Fis, BR-30123970 Belo Horizonte, MG - Brazil

^[3] Univ Fed Ceara, Dept Fis, BR-60455900 Fortaleza, Ceara - Brazil

^[4] Univ Antwerp, Dept Phys, B-2020 Antwerp - Belgium

• Document type: Journal article
• Source: ACS NANO; v. 15, n. 9, p. 15371-15380, SEP 28 2021.
• Web of Science Citations: 0

Abstract

The Stark effect is one of the most efficient mechanisms to manipulate many-body states in nanostructured systems. In mono- and few-layer transition metal dichalcogenides, it has been successfully induced by optical and electric field means. Here, we tune the optical emission energies and dissociate excitonic states in MoSe2 monolayers employing the 220 MHz in-plane piezoelectric field carried by surface acoustic waves. We transfer the monolayers to high dielectric constant piezoelectric substrates, where the neutral exciton binding energy is reduced, allowing us to efficiently quench (above 90%) and red-shift the excitonic optical emissions. A model for the acoustically induced Stark effect yields neutral exciton and trion in-plane polarizabilities of 530 and 630 x 10(-5) meV/(kV/cm)(2), respectively, which are considerably larger than those reported for monolayers encapsulated in hexagonal boron nitride. Large in-plane polarizabilities are an attractive ingredient to manipulate and modulate multiexciton interactions in two-dimensional semiconductor nanostructures for optoelectronic applications. (AU)

• FAPESP's process: 19/13654-5 - Fabrication and characterization of unidirectional transducers for surface acoustic wave generation
• Grantee: Luca de Oliveira Trinchão
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 12/11382-9 - Optical modulation of semiconductor nanostructures using surface acoustic waves
• Grantee: Odilon Divino Damasceno Couto Júnior
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 18/18091-6 - Micro-photoluminescence surface mapping under surface acoustic wave modulation
• Grantee: Matheus Finamor
• Support Opportunities: Scholarships in Brazil - Scientific Initiation