Terahertz-Rate Kerr-Microresonator Optical Clockwork

Area of Science:

• Photonics and Optical Engineering
• Quantum Optics
• Metrology

Background:

• Kerr microresonators utilize nonlinear optics to generate fundamental states of light.
• Photonic integration enables low-noise, compact, and power-efficient devices.
• Kerr solitons in microresonators produce ultrafast pulse trains and broadband optical frequency combs.

Purpose of the Study:

• To introduce a Kerr-microresonator optical clockwork for distributing optical clock signals.
• To demonstrate a foundational device for advanced optical metrology.
• To explore new possibilities in high-performance optical clock measurements.

Main Methods:

• Fabrication of a silicon nitride (Si₃N₄) microresonator.
• Generation of a Kerr-soliton frequency comb with a 1 THz repetition frequency.
• Electro-optic modulation with microwave signals for measurement and arbitrary frequency comb generation via EO phase modulation.

Main Results:

• Characterization of the Kerr-microresonator optical clockwork.
• Achieved absolute frequency noise measurement of 1 part in 10¹⁷.
• Demonstrated arbitrary generation of CW modes to reduce repetition frequency and enhance comb resolution.

Conclusions:

• The developed Kerr-microresonator optical clockwork represents a significant advancement in optical timing technology.
• The achieved accuracy and precision open new avenues for measuring high-performance optical clocks.
• This technology enables optical-based timing experiments in wideband and high-speed frequency ranges.