Single Quantum Dot Selection and Tailor-Made Photonic Device Integration using a Nanoscale-Focus Pinspot

Area of Science:

• Quantum photonics
• Semiconductor device fabrication
• Nanotechnology

Background:

• Semiconductor quantum dots (QDs) are promising for quantum light sources due to brightness and scalability.
• Spatial and spectral randomness of QDs limits large-scale quantum photonic platform construction.
• Deterministic integration of QDs with photonic structures is crucial.

Purpose of the Study:

• To present a methodology for the deterministic integration of single QDs with custom photonic structures.
• To overcome the limitations of QD randomness in building scalable quantum photonic devices.

Main Methods:

• Utilized nanoscale-focus pinspot (NFP) with helium-ion microscopy for nondestructive luminescence picking.
• Reduced QD density while preserving the surrounding medium to isolate single QD emissions.
• Designed and integrated a circular Bragg reflector (CBR) with selected QDs.
• Demonstrated in-situ fabrication of photonic devices on target QDs.

Main Results:

• Achieved deterministic integration of single QDs with tailor-made photonic structures.
• Improved QD emission extraction efficiency by 25 times after CBR integration.
• NFP method demonstrated applicability to various photonic structures (waveguides, cavities) without medium destruction.

Conclusions:

• The presented methodology enables deterministic fabrication of photonic devices on target QDs.
• NFP combined with CBR integration significantly enhances light extraction efficiency.
• This approach is versatile and applicable to diverse photonic structures and materials for quantum technologies.