Third-order nonlinearity OPO: Schmidt mode decomposition and tripartite entanglement.

Area of Science:

• Quantum optics
• Nonlinear optics
• Solid-state physics

Background:

• Optical parametric oscillators (OPOs) are crucial for generating specific light frequencies.
• Third-order nonlinearities (χ(3)) in optical media enable complex light-matter interactions.
• On-chip implementations, particularly CMOS-compatible ones, are advancing integrated photonic technologies.

Purpose of the Study:

• To investigate the quantum properties of light within OPOs.
• To determine the conditions for generating quantum entanglement in such systems.
• To assess the relevance of these findings for emerging integrated photonic devices.

Main Methods:

• Theoretical investigation of light propagation in nonlinear media.
• Analysis of four-wave mixing gain processes.
• Modeling of quantum entanglement generation above the OPO threshold.

Main Results:

• Bipartite and tripartite quantum entanglement are predicted to exist in OPOs above threshold.
• The generation of entanglement is shown to be robust despite competing nonlinear effects like phase modulation.
• The findings highlight the potential for generating entangled photons in integrated OPO platforms.

Conclusions:

• OPOs based on third-order nonlinearities can generate significant quantum entanglement.
• These results are directly applicable to the development of CMOS-compatible on-chip OPOs.
• The study provides a theoretical foundation for future experimental demonstrations of quantum light sources on photonic chips.