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Excitonic transport driven by repulsive dipolar interaction in a van der Waals heterostructure
Zhe Sun1,2, Alberto Ciarrocchi1,2, Fedele Tagarelli1,2
1Institute of Electrical and Microengineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Nature Photonics
|January 7, 2022
Summary
Repulsive dipolar interactions significantly boost interlayer exciton mobility in dilute gases. This finding enhances understanding of quantum many-body physics and could lead to new excitonic devices.
Area of Science:
- Quantum physics
- Condensed matter physics
- Materials science
Background:
- Dipolar bosonic gases are crucial for studying quantum many-body physics.
- Experimental systems include Rydberg atoms, quantum wells, and van der Waals heterostructures.
- Interactions in dilute gases can lead to phenomena like Bose-Einstein condensation.
Purpose of the Study:
- Investigate the impact of repulsive dipolar interactions on interlayer exciton dynamics.
- Quantify the effect of these interactions on exciton transport and mobility.
- Explore potential applications in excitonic devices.
Main Methods:
- Utilized spatial and time-resolved photoluminescence imaging.
- Observed exciton transport dynamics in a dilute regime.
- Estimated exciton mobility directly from experimental data.
Main Results:
- Repulsive dipolar interactions significantly alter diffusive exciton transport.
- Interactions act as a drift force, enhancing the diffusion coefficient by an order of magnitude.
- Demonstrated electrical control over interlayer excitons.
Conclusions:
- Repulsive dipolar interactions are key to understanding exciton dynamics in dilute systems.
- Enhanced exciton mobility opens new avenues for designing advanced excitonic devices.
- This research bridges fundamental quantum physics with practical device applications.
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