Electrically Controlled Excitons, Charge Transfer Induced Trions, and Narrowband Emitters in MoSe2–WSe2 Lateral Heterostructure
Year: 2024
Type: article
Abstract: Controlling excitons and their transport in two-dimensional (2D) transition metal dichalcogenide heterostructures is central to advancing photonics and electronics on-chip integration. We investigate the controlled generation and manipulation of excitons and their complexes in monolayer MoSe 2 –WSe 2 lateral heterostructures (LHSs). Incorporating graphene as a back gate and edge contact in a field-effect transistor geometry, we achieve the precise electrical tuning of exciton complexes and their transfer across interfaces. Photoluminescence and photocurrent maps at 4 K reveal the synergistic effect of the local electric field and interface phenomena in the modulation of excitons, trions, and free carriers. We observe spatial variations in the exciton and trion densities driven by exciton–trion conversion under electrical manipulation. Additionally, we demonstrate controlled narrow-band emissions within the LHS through carrier injection and electrical biasing. Density functional theory calculation reveals significant band modification at the lateral interfaces. This work advances exciton manipulation in LHS and shows promise for next-generation 2D quantum devices.
Source: Nano Letters
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Funders: Australian Government, Department of Science and Technology, Ministry of Science and Technology, India, Deutsche Forschungsgemeinschaft, Bundesministerium für Bildung und Forschung, Indian Institute of Technology Kharagpur, Ministerium für Kultur und Wissenschaft des Landes Nordrhein-Westfalen, Science and Engineering Research Board, Bhabha Atomic Research Centre
OpenAlex ID: W4404242901