Bandwidth shaping of microresonator-based frequency combs via dispersion engineering

Area of Science:

• Optics and Photonics
• Nonlinear Optics
• Quantum Optics

Background:

• Microresonator-based parametric frequency combs are crucial for applications requiring precise optical frequencies.
• Dispersion, particularly group-velocity and higher-order dispersion, significantly influences the spectral properties of these combs.
• Understanding these dispersive effects is key to controlling comb bandwidth and power.

Purpose of the Study:

• To experimentally and theoretically investigate the impact of group-velocity dispersion and higher-order dispersion on the bandwidth of microresonator-based parametric frequency combs.
• To demonstrate the ability to tailor comb bandwidth and power for specific applications by controlling dispersion.
• To elucidate the critical role of fourth-order dispersion in achieving octave-spanning frequency combs.

Main Methods:

• Experimental measurements of frequency comb spectra generated in microresonators.
• Theoretical modeling incorporating group-velocity and higher-order dispersion effects.
• Systematic variation of dispersion parameters to study their influence on comb properties.

Main Results:

• The spectral bandwidth and power of microresonator frequency combs can be precisely controlled.
• Group-velocity dispersion and higher-order dispersion are identified as key parameters for tailoring comb characteristics.
• Fourth-order dispersion is shown to be critically important for generating octave-spanning frequency combs.

Conclusions:

• Dispersion engineering offers a powerful method for optimizing microresonator frequency combs for diverse applications.
• The findings provide a pathway for designing microresonators with tailored dispersive properties.
• Achieving broadband, octave-spanning frequency combs relies heavily on managing higher-order dispersion, particularly fourth-order effects.