Control of Hybrid Exciton Lifetime in MoSe/WS Moiré Heterostructures.

Adv Sci (Weinh)

State Key Laboratory of Tribology in Advanced Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing, 100084, China.

Published: September 2024

AI Article Synopsis

  • Hybrid excitons are promising for use in semiconductors due to their strong oscillation strength and long lifetimes, making them ideal for information transfer in exciton-based devices.
  • The research involves modifying layer hybridization in MoSe/WS heterostructures using electric fields, successfully regulating the exciton lifetime from 1.36 to 4.60 ns.
  • Findings highlight the impact of electric fields and excitation power on hybrid exciton lifetimes, which is crucial for developing efficient optoelectronic devices using transition-metal dichalcogenide materials.

Article Abstract

Hybrid excitons, characterized by their strong oscillation strength and long lifetimes, hold great potential as information carriers in semiconductors. They offer promising applications in exciton-based devices and circuits. MoSe/WS heterostructures represent an ideal platform for studying hybrid excitons, but how to regulate the exciton lifetime has not yet been explored. In this study, layer hybridization is modulated by applying electric fields parallel or antiparallel to the dipole moment, enabling us to regulate the exciton lifetime from 1.36 to 4.60 ns. Furthermore, the time-resolved photoluminescence decay traces are measured at different excitation power. A hybrid exciton annihilation rate of 8.9 × 10 cm s is obtained by fitting. This work reveals the effects of electric fields and excitation power on the lifetime of hybrid excitons in MoSe/WS 1.5° moiré heterostructures, which play important roles in high photoluminescence quantum yield optoelectronic devices based on transition-metal dichalcogenides heterostructures.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11425870PMC
http://dx.doi.org/10.1002/advs.202403127DOI Listing

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