English

Impact of higher-order dispersion on frequency-modulated combs

Optics 2023-10-17 v1 Applied Physics

Abstract

Frequency-modulated (FM) combs form spontaneously in free-running semiconductor lasers and possess a vast potential for spectroscopic applications. Despite recent progress in obtaining a conclusive theoretical description, experimental FM combs often exhibit non-ideal traits, which prevents their widespread use. Here we explain this by providing a clear theoretical and experimental study of the impact of the higher-order dispersion on FM combs. We reveal that spectrally-dependent dispersion is detrimental for comb performance and leads to a decreased comb bandwidth and the appearance of spectral holes. These undesirable traits can be mended by applying a radio-frequency modulation of the laser bias. We show that electrical injection-locking of the laser leads to a significant increase of the comb bandwidth, a uniform-like spectral amplitudes, and the rectification of the instantaneous frequency to recover a nearly linear frequency chirp of FM combs.

Keywords

Cite

@article{arxiv.2310.09915,
  title  = {Impact of higher-order dispersion on frequency-modulated combs},
  author = {Nikola Opačak and Barbara Schneider and Jérôme Faist and Benedikt Schwarz},
  journal= {arXiv preprint arXiv:2310.09915},
  year   = {2023}
}