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Valley-Engineered Landau Polaritons in a van der Waals Semiconductor Microcavity
Xinyue Zhang1, Hongming Zhang1, Yaofeng Zhu1
1Xiamen University, Department of Physics, College of Physical Science and Technology, Xiamen 361005, China.
Physical Review Letters
|August 10, 2026
Summary
Researchers created Landau polaritons in 2D tungsten diselenide (WSe_{2}) within an optical microcavity. These hybrid light-matter quasiparticles show valley-dependent control, enabling new quantum phase manipulation.
Area of Science:
- Quantum Optics
- Condensed Matter Physics
- Materials Science
Background:
- Two-dimensional (2D) materials offer unique platforms for quantum phenomena.
- Interactions between light and quantum matter are key to exploring emergent behaviors.
- Optical microcavities enhance light-matter interactions.
Purpose of the Study:
- To realize and investigate Landau polaritons in a monolayer tungsten diselenide (WSe_{2}) system.
- To explore the coupling between cavity photons and Landau level transitions.
- To demonstrate control over Landau polaritons using the valley degree of freedom.
Main Methods:
- Integration of monolayer WSe_{2} into an optical microcavity.
- Embedding a two-dimensional electron gas (2DEG) and applying a magnetic field.
- Studying strong coupling between photons and interband Landau level (LL) transitions.
Main Results:
- Achieved strong coupling, forming hybrid light-matter quasiparticles (Landau polaritons).
- Observed valley-dependent oscillations in coupling strengths and energies.
- Demonstrated nonlinear renormalization of LL transitions and coupling strengths due to intervalley correlations.
Conclusions:
- Established a new paradigm for cavity quantum electrodynamics in 2D systems.
- Showcased valley control of Landau polaritons.
- Opened avenues for light-mediated manipulation of quantum phases in correlated 2D materials.
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