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Updated: Jun 6, 2025
08:04
Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
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Acoustic Modulation of Excitonic Complexes in hBN/WSe2/hBN Heterostructures
Marcos L F Gomes1, Pedro W Matrone1, Alisson R Cadore2
1Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin, 13083-859 Campinas, Brazil.
Nano Letters
|November 25, 2024
Summary
Surface acoustic waves (SAWs) interact differently with excitons in van der Waals heterostructures. Charged excitons and biexcitons show stronger SAW interaction than neutral excitons, crucial for 2D optoelectronics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Optics
Background:
- Van der Waals heterostructures (vdWHs) enable novel quantum phenomena.
- Excitons, trions, and biexcitons are key quasiparticles in 2D materials.
- Surface acoustic waves (SAWs) offer a tunable stimulus for exploring quantum effects.
Purpose of the Study:
- Investigate the interaction between SAWs and various excitonic species in a hBN/WSe2/hBN vdWH.
- Understand the temperature-dependent behavior of excitons under SAW influence.
- Explore the potential of SAW modulation for 2D materials-based devices.
Main Methods:
- Utilized a hBN/WSe2/hBN van der Waals heterostructure.
- Applied high-frequency surface acoustic waves (SAWs) as a stimulus.
- Performed low-temperature (5 K) and room-temperature measurements.
Main Results:
- Neutral excitons exhibit weak response to SAWs at 5 K.
- Charged excitonic complexes (trions, biexcitons) interact more strongly with SAW piezoelectric fields.
- At room temperature, SAWs have a dual role, influenced by photodoping and metastable states.
Conclusions:
- SAW interaction with excitonic complexes in vdWHs is complex and temperature-dependent.
- Charged excitons and biexcitons are more sensitive to SAWs than neutral excitons.
- SAW modulation offers potential for advanced 2D optoelectronic and energy harvesting applications.
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