Additive GaN Solid Immersion Lenses for Enhanced Photon Extraction Efficiency from Diamond Color Centers

Area of Science:

• Quantum optics
• Solid-state physics
• Materials science

Background:

• Efficient light extraction from solid-state spin centers is crucial for quantum systems.
• Nitrogen-vacancy (NV) centers in diamond are promising solid-state spin qubits.

Purpose of the Study:

• To enhance fluorescent light collection efficiency from NV centers in diamond.
• To enable deterministic fabrication routes for scalable quantum systems.

Main Methods:

• Laser-writing of NV centers in bulk diamond.
• Micro-transfer printing of gallium nitride (GaN) solid immersion lenses.
• Noninvasive integration of micro-lenses via van der Waals forces.

Main Results:

• Approximately 2x improvement in fluorescent light collection efficiency for NV centers at 5 μm depth with NA = 0.95 objective.
• Significant enhancement of light collection and signal-to-noise ratio with NA = 0.5 objective.
• Preservation of NV center quantum properties after micro-lens integration.

Conclusions:

• Micro-transfer printed GaN solid immersion lenses effectively enhance light extraction from NV centers in diamond.
• The integration method is noninvasive and compatible with scalable quantum system development.
• This approach offers a promising route for improving the performance of diamond-based quantum technologies.