Quantum mechanics

Voltage

Engineering

Frequency comb

Cosmology

Bandwidth (computing)

Materials science

Telecommunications

Low voltage

Laser

Insertion loss

Physics

Optics

Comb generator

Lithium niobate

Flatness (cosmology)

Chip

Optoelectronics

Electrical engineering

Journal of Lightwave Technology

Chip-scale electro-optic (EO) frequency combs are expected to play an essential role in future high-capacity optical communications systems and next-generation mobile communications. The application requires integrated EO frequency comb generators featuring good spectral flatness, high modulation bandwidth, low driving voltage and low insertion loss simultaneously. Here, we demonstrate a flat-top optical flat comb (OFC) generator based on high-performance lithium niobate on insulator modulators. The OFC generator shows a low on-chip loss (2.1 dB), a low driving voltage over a broad frequency range, and a large 3-dB EO bandwidth. Moreover, with consuming power of less than 2W, the presented device produces 13 lines with a power variation of less than 1.2 dB and a line spacing of 31 GHz which can further be extended to 67 GHz.

Flat Optical Frequency Comb Generator Based on Integrated Lithium Niobate Modulators