Weakly Dispersive Band in Synthetic Moiré Superlattice Inducing Optimal Compact Comb Generation

Area of Science:

• Condensed Matter Physics
• Photonics
• Wave Phenomena

Background:

• Moiré superlattices exhibit exotic physics with applications in electronics and photonics.
• Research has focused on wave localization in flat bands and delocalization in dispersive bands.

Purpose of the Study:

• Investigate wave packet distributions in the weakly dispersive band of a 1D synthetic frequency moiré superlattice.
• Explore novel frequency comb generation using these unique band properties.

Main Methods:

• Studied a one-dimensional synthetic frequency moiré superlattice.
• Analyzed wave packet distributions within the weakly dispersive band regime.
• Investigated mode couplings arising from unequal sublattice periods.

Main Results:

• Observed reduced mode spacing in spectral wave packets compared to individual ring free spectral range.
• Identified optimal compact frequency comb generation in the weakly dispersive regime.
• Demonstrated that optimal combs benefit from uniform power distribution and broad frequency spanning.

Conclusions:

• The study elucidates the fundamental physics of weakly dispersive moiré bands in synthetic frequency dimensions.
• Presents a novel approach for compact frequency comb generation in on-chip devices.
• Highlights the interplay between band flatness and mode distribution uniformity for comb generation.