Room-temperature strong coupling in a single-photon emitter-metasurface system

Area of Science:

• Quantum optics and photonics
• Solid-state quantum emitters
• Cavity quantum electrodynamics

Background:

• Solid-state single-photon sources (SPEs) are crucial for quantum technology, requiring isolation from environmental decoherence.
• Interfacing SPEs with high-finesse cavities is necessary for strong coupling, enabling mediated interactions via cavity fields.
• Achieving strong coupling at higher temperatures is difficult due to competing incoherent processes.

Purpose of the Study:

• To overcome the challenge of achieving strong coupling at elevated temperatures for quantum applications.
• To demonstrate a quantum system combining SPEs in hexagonal boron nitride with bound states in the continuum (BIC) dielectric cavities.
• To enable scalable quantum devices operating at room temperature.

Main Methods:

• Utilized a quantum system comprising single-photon emitters in hexagonal boron nitride.
• Employed a dielectric cavity based on bound states in the continuum (BIC) for efficient photon trapping.
• Experimentally investigated the strong coupling regime between the SPEs and the BIC cavity.

Main Results:

• Demonstrated strong coupling at room temperature with a significant Rabi splitting of approximately 4 meV.
• Attributed the strong coupling to the combination of narrow linewidth and high oscillator strength of the SPEs.
• Highlighted the role of the BIC cavity in efficient photon trapping, facilitating the observed strong coupling.

Conclusions:

• The study successfully achieved room-temperature strong coupling, a critical step for practical quantum technologies.
• Findings pave the way for advancing the understanding of quantum dynamics in the strong coupling regime.
• Enables the development of scalable quantum devices that can operate effectively outside of cryogenic conditions.