Purcell-Induced Bright Single Photon Emitters in Hexagonal Boron Nitride

Area of Science:

• Quantum Photonics
• Materials Science
• Nanotechnology

Background:

• Single-photon emitters (SPEs) in hexagonal boron nitride (hBN) are crucial for room-temperature quantum photonic technologies.
• Challenges include slow radiative decay and difficult emitter placement, hindering practical applications.

Purpose of the Study:

• To engineer emitter-cavity coupling using plasmonic nanoresonators (PNRs) to enhance room-temperature SPEs in hBN.
• To overcome limitations of slow decay and nondeterministic placement for scalable quantum systems.

Main Methods:

• Fabrication of large-area arrays of gold-coated silicon pillars with alumina spacers.
• Integration with native hBN defects to create PNRs for Purcell enhancement.
• Characterization of SPE brightness, emission rate, lifetime, and yield.
• Density functional theory (DFT) to analyze emitter-metal interactions.

Main Results:

• Achieved a 10-fold local-field enhancement in the hBN emission band.
• Observed bright SPEs with average saturated emission rates exceeding 5 million counts per second.
• Demonstrated an average SPE lifetime of less than 0.5 ns and a 29% yield.
• DFT confirmed alumina spacer mitigates electronic broadening from metal proximity.

Conclusions:

• Demonstrated arrays of bright, heterogeneously integrated single-photon sources using PNR-enhanced hBN SPEs.
• The engineered emitter-cavity coupling and enhanced radiative emission pave the way for robust, scalable quantum information systems.
• Alumina spacer is critical for preserving emission quality in proximity to plasmonic structures.