Rydberg exciton-polaritons in a Cu₂O microcavity

Area of Science:

• Solid-state physics
• Quantum optics
• Materials science

Background:

• Giant Rydberg excitons, with diameters up to 1 μm, have been observed in cuprous oxide (Cu2O).
• These large excitons offer enhanced interactions, crucial for developing strongly correlated solid-state platforms.
• Rydberg exciton-polaritons, formed by coupling excitons to cavity photons, are a promising avenue, but achieving strong coupling has been challenging.

Purpose of the Study:

• To achieve strong coupling between Rydberg excitons and cavity photons in a Cu2O microcavity.
• To demonstrate the formation of Rydberg exciton-polaritons in this system.
• To explore the potential for scalable, strongly correlated solid-state platforms.

Main Methods:

• Embedding a thin Cu2O crystal into a Fabry-Pérot microcavity.
• Utilizing optical spectroscopy to probe exciton-photon interactions.
• Achieving strong coupling regime for Rydberg excitons up to n=6.

Main Results:

• Demonstrated strong coupling of light to Cu2O Rydberg excitons up to the principal quantum number n=6.
• Successfully formed Cu2O Rydberg exciton-polaritons.
• Observed significant enhancements in excitonic interactions due to giant exciton dimensions.

Conclusions:

• The study successfully achieved strong coupling of Rydberg excitons in Cu2O, forming exciton-polaritons.
• This work provides a pathway towards scalable, strongly correlated solid-state systems.
• The findings open possibilities for exploring novel quantum phenomena using light on a chip.