Exploring nonlinearity-loss tradeoffs in foundry fabricated silicon integrated photon pair sources

Area of Science:

• Quantum photonics
• Integrated photonics
• Semiconductor device fabrication

Background:

• Foundry-fabricated silicon heralded photon pair sources are crucial for quantum photonics.
• Traditional silicon photonics platforms (<0.2 μm² waveguide cross-sections) suffer from enhanced surface absorption and scattering losses.
• Minimizing optical loss is critical for quantum information applications.

Purpose of the Study:

• To investigate photon pair generation in a low-loss, thick (3 μm) silicon foundry platform.
• To analyze the trade-offs between nonlinearity, loss, and footprint in thick silicon waveguides.
• To determine the optimal silicon thickness for resonator-based photon pair sources.

Main Methods:

• Fabrication of silicon waveguides with a 3 μm thickness in a standard foundry process.
• Characterization of optical loss, including surface scattering and absorption.
• Measurement of nonlinear optical effects for photon pair generation.
• Analysis of the relationship between waveguide dimensions, loss, and nonlinear efficiency.

Main Results:

• Thicker silicon waveguides (3 μm) demonstrate reduced optical loss compared to traditional thin platforms.
• Exploration of nonlinearity-loss-footprint trade-offs reveals potential for improved photon pair generation efficiency.
• Initial findings suggest thicker silicon is advantageous for resonator-based sources.

Conclusions:

• A thick (3 μm) silicon foundry platform offers a promising route to low-loss photon pair sources.
• Optimizing silicon waveguide thickness is key to balancing nonlinearity, loss, and footprint for quantum applications.
• Further research into resonator designs on thick silicon platforms is warranted.