Spontaneous Exciton Valley Coherence in Transition Metal Dichalcogenide Monolayers Interfaced with an Anisotropic
Pankaj K Jha1, Nir Shitrit1, Xuexin Ren1
1NSF Nanoscale Science and Engineering Center (NSEC), 3112 Etcheverry Hall, University of California, Berkeley, California 94720, USA.
Physical Review Letters
|September 29, 2018
Summary
Researchers demonstrate spontaneous generation of exciton intervalley coherence in transition metal dichalcogenides monolayers. This breakthrough, achieved without external fields, paves the way for advanced quantum valleytronic devices.
Area of Science:
- Quantum physics
- Materials science
- Condensed matter physics
Background:
- Transition metal dichalcogenides (TMDs) monolayers are promising for quantum information science due to controllable exciton intervalley coherence.
- Current methods for generating intervalley coherence require an external coherent field, limiting practical applications.
Purpose of the Study:
- To theoretically demonstrate the spontaneous generation of exciton intervalley coherence in TMD monolayers.
- To explore a novel method for achieving quantum coherence without external fields.
Main Methods:
- Theoretical modeling of exciton dynamics in TMD monolayers.
- Designing a polarization-dependent metasurface to manipulate vacuum fields.
- Inducing anisotropic decay rates for in-plane excitonic dipoles.
Main Results:
- Successful theoretical demonstration of spontaneous exciton intervalley coherence generation.
- Metasurface design enables control over vacuum field interactions.
- Anisotropic decay rates are shown to be key to inducing coherence.
Conclusions:
- Spontaneous generation of exciton intervalley coherence is achievable in TMDs.
- Metasurface-engineered vacuum fields offer a new route for quantum control.
- This work opens possibilities for novel quantum valleytronic devices.
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