Efficient Transverse Multiwave Interactions up to Six-Wave Mixing in a High-Q Lithium Niobate Microresonator

Area of Science:

• Nonlinear optics
• Quantum technologies
• Photonics

Background:

• High-order nonlinear optical processes are vital for UV light sources and quantum technologies.
• Practical implementation is hindered by weak nonlinear susceptibilities and phase-matching challenges.
• Existing microresonator approaches face limitations in overcoming these hurdles.

Purpose of the Study:

• To propose and demonstrate a breakthrough transverse multiwave mixing scheme.
• To overcome limitations in high-order nonlinear optics using a single continuous-wave laser pump.
• To enable efficient UV light generation and advance quantum technologies.

Main Methods:

• Utilized a high-Q lithium niobate microresonator.
• Employed a single continuous-wave laser pump at 1546 nm.
• Leveraged self-organized subwavelength photorefractive gratings (SPGs) generated via bidirectional stimulated Raman scattering (SRS).
• Implemented a transverse multiwave mixing architecture with SPG-mediated momentum engineering.

Main Results:

• Achieved broadband phase-matching and preserved ultrahigh Q-factor (>7x10^6).
• Demonstrated simultaneous sum-frequency generation to six-wave mixing processes over a 500-nm bandwidth.
• Reported the first single-pump phase-matched transverse SFG with record 590%/W conversion efficiency.
• Enabled transverse multiwave mixing from χ(3) to χ(5) using a single cw pump.
• Successfully generated visible and UV light with high efficiency.

Conclusions:

• The proposed transverse multiwave mixing scheme overcomes key limitations in high-order nonlinear optics.
• This approach enables efficient generation of visible and UV light from a single pump source.
• Represents a significant advancement in integrated nonlinear photonics and quantum technology applications.