Real-time high-resolution heterodyne-based measurements of spectral dynamics in fibre lasers


Conventional tools for measurement of laser spectra (e.g. optical spectrum analysers) capture data averaged over a considerable time period. However, the generation spectrum of many laser types may involve spectral dynamics whose relatively fast time scale is determined by their cavity round trip period, calling for instrumentation featuring both high temporal and spectral resolution. Such real-time spectral characterisation becomes particularly challenging if the laser pulses are long, or they have continuous or quasi-continuous wave radiation components. Here we combine optical heterodyning with a technique of spatiooral intensity measurements that allows the characterisation of such complex sources. Fast, round-trip-resolved spectral dynamics of cavity-based systems in real-time are obtained, with temporal resolution of one cavity round trip and frequency resolution defined by its inverse (85 ns and 24 MHz respectively are demonstrated). We also show how under certain conditions for quasi-continuous wave sources, the spectral resolution could be further increased by a factor of 100 by direct extraction of phase information from the heterodyned dynamics or by using double time scales within the spectrogram approach.

Publication DOI:
Divisions: College of Engineering & Physical Sciences
College of Engineering & Physical Sciences > Aston Institute of Photonics Technology (AIPT)
Additional Information: This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit Funding: ERC (project UltraLaser); Horizon 2020 project CARDIALLY; Russian Ministry of Education and Science (14.584.21.0014); Russian Foundation for Basic Research (15-02-07925, 16-32-60153, 14-42-08026 and 14-02-00449А). Supplementary information accompanies this paper at
Uncontrolled Keywords: General
Publication ISSN: 2045-2322
Last Modified: 17 Jun 2024 07:19
Date Deposited: 18 May 2016 13:00
Full Text Link: http://www.natu ... icles/srep23152
Related URLs: http://www.scop ... tnerID=8YFLogxK (Scopus URL)
PURE Output Type: Article
Published Date: 2016-03-17
Accepted Date: 2016-02-29
Submitted Date: 2015-09-11
Authors: Sugavanam, Srikanth
Fabbri, Simon (ORCID Profile 0000-0003-1858-4211)
Le, Son Thai (ORCID Profile 0000-0002-3824-9456)
Lobach, Ivan
Kablukov, Sergey
Khorev, Serge
Churkin, Dmitry



Version: Published Version

License: Creative Commons Attribution

Export / Share Citation


Additional statistics for this record