High-Quality GaP(111) Grown by Gas-Source MBE for Photonic Crystals and Advanced Nonlinear Optical Applications.

Area of Science:

• Semiconductor physics
• Materials science
• Photonics

Background:

• Precise fabrication of semiconductor photonic crystals is crucial for advanced photonic devices.
• Gallium Phosphide (GaP) exhibits a high refractive index, wide optical bandgap, and optical anisotropy, making it suitable for photonic applications.
• GaP's near-lattice matching with silicon substrates facilitates integration with silicon-based technologies.

Purpose of the Study:

• To present the growth of high-quality Gallium Phosphide (GaP)(111) thin films.
• To demonstrate the fabrication of GaP(111) photonic crystal cavities.
• To highlight the potential of GaP(111) for advanced photonic applications.

Main Methods:

• Gas-source molecular-beam epitaxy (GSMBE) for GaP(111) thin film growth.
• Homo-epitaxy to achieve atomically smooth terraces.
• Fabrication of photonic crystal cavities using AlGaP(111) as a sacrificial layer.

Main Results:

• Achieved high-quality GaP(111) thin films with atomically smooth terraces.
• Fabricated GaP(111) photonic crystal cavities.
• Obtained a quality factor of 1200 for the cavity mode with resonance around 1500 nm.

Conclusions:

• GaP(111) is a promising material for advanced photonic architectures.
• The demonstrated GaP(111) photonic crystal cavities show potential for strong light confinement.
• This work supports applications in nonlinear optics, including second-harmonic and sum-frequency generation.