Shutter-Synchronized Molecular Beam Epitaxy for Wafer-Scale Homogeneous GaAs and Telecom Wavelength Quantum Emitter...

Area of Science:

• Quantum Information Science
• Materials Science
• Nanotechnology

Background:

• Current quantum dot (QD) devices rely on random nucleation, leading to unpredictable emission wavelengths.
• Deterministic growth of QDs in both position and emission wavelength is essential for industrial-scale manufacturing.

Purpose of the Study:

• To develop a method for deterministic quantum dot growth with precise control over position and emission wavelength.
• To achieve narrow emission wavelength homogeneity for scalable quantum device fabrication.

Main Methods:

• Utilizing local droplet etching during molecular beam epitaxy for controlled QD nucleation.
• Implementing wafer rotation-synchronized shutter timing and adapted growth parameters for wavelength control.
• Employing nanohole drilling and InAs infilling for O-band emission QDs.

Main Results:

• Achieved narrow peak emission wavelength homogeneity (<1.2 nm shift over 45 mm) and inhomogeneous broadening (2 nm at 4 K) for strain-free GaAs QDs.
• Demonstrated QD growth with emission wavelengths <800 nm, suitable for quantum optics and memory.
• Produced O-band emitting QDs (~1.3 µm) with superior wavelength and density homogeneity compared to standard methods.

Conclusions:

• Local droplet etching provides excellent density control and predetermines QD nucleation sites.
• Deterministic QD growth offers significant advantages in wavelength homogeneity and scalability for quantum technologies.
• The developed methods pave the way for high-yield wafer-scale manufacturing of quantum dot devices.