English

Evidence of Linear Chirp in Mid-Infrared Quantum Cascade Lasers

Optics 2018-04-13 v1

Abstract

We measure the inter-modal phase relation of a quantum cascade laser frequency comb operating at 8 um using a coherent beatnote spectroscopy. We find these phases to be reproducible after cycling the power of the device, and to be smoothly varying with driving current. Moreover, these phases describe a comb state exhibiting a simple, linear chirp, which in fact corresponds to the lowest state of chirp to minimise the amplitude modulation, as required for combs driven by four wave mixing in a gain medium with a short gain recovery lifetime.

Keywords

Cite

@article{arxiv.1804.04162,
  title  = {Evidence of Linear Chirp in Mid-Infrared Quantum Cascade Lasers},
  author = {Matthew Singleton and Pierre Jouy and Mattias Beck and Jérôme Faist},
  journal= {arXiv preprint arXiv:1804.04162},
  year   = {2018}
}