English

Phase-sensitive characterization of a quantum frequency converter by spectral interferometry

Quantum Physics 2026-02-09 v1 Optics

Abstract

We introduce an experimental technique for complete phase-sensitive characterization of arbitrary unitary spectral-temporal transformations of optical modes. Our method recovers the complex spectral transfer function, or Green's function, of a frequency converter by analyzing spectral interference in the response to a tunable bichromatic probe. We perform a proof-of-concept experiment on a frequency conversion module based on Bragg-scattering four-wave mixing in photonic crystal fiber. Our results validate our technique by recovering useful information in the phase of the Green's function, revealing the relative positions of regions of active frequency conversion and passive dispersive propagation within the module. Our work introduces a new approach to characterizing the performance of a variety of active devices with diverse applications in emerging quantum technologies.

Keywords

Cite

@article{arxiv.2602.06796,
  title  = {Phase-sensitive characterization of a quantum frequency converter by spectral interferometry},
  author = {Mateusz J Olszewski and Kasper Hecht Alexander and Michael T M Woodley and Leah R Murphy and Peter J Mosley and Alex O C Davis},
  journal= {arXiv preprint arXiv:2602.06796},
  year   = {2026}
}

Comments

14 pages, 17 figures

R2 v1 2026-07-01T10:24:38.388Z