SLM phase mask optimization for fiber OAM mode excitation

  • Antonio Astorino (Invited author)
  • , Andrew Rafael Bañas (Invited author)
  • , Karsten Rottwitt (Invited author)
  • , Jesper Glückstad (Invited author)

    Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review

    599 Downloads (Orbit)

    Abstract

    Fiber orbital angular momentum (OAM) modes can be employed in mode-division multiplexing to increase the channel capacity in optical communication systems. Over the years, several experiments to excite high-purity OAM modes by using one phase-only spatial light modulator (SLM) have been conducted. Since phase-only SLMs are intrinsically imperfect for this purpose due to the impossibility to simultaneously modulate both amplitude and phase in the light source, optimal phase masks need to be generated by iterative algorithms. However, if the state of every pixel in the mask is an unknown of the problem, the computational cost is extremely high. The system circular symmetry can be exploited to overcome this issue. Here, for the first time, this approach is implemented and a simple machine learning algorithm is developed to calculate optimal phase masks with a low number of unknowns and iterations. Simulated and experimental results show that the developed technique is capable of exciting high-purity OAM modes.
    Original languageEnglish
    Title of host publicationProceedings of SPIE
    EditorsJesper Glückstad, David L. Andrews, Enrique J. Galvez
    Number of pages8
    Volume10935
    PublisherSPIE - International Society for Optical Engineering
    Publication date2019
    Article number109350F
    DOIs
    Publication statusPublished - 2019
    EventSPIE Photonics West OPTO 2019 - The Moscone Center, San Francisco, United States
    Duration: 2 Feb 20197 Feb 2019

    Conference

    ConferenceSPIE Photonics West OPTO 2019
    LocationThe Moscone Center
    Country/TerritoryUnited States
    CitySan Francisco
    Period02/02/201907/02/2019
    SponsorSPIE
    SeriesProceedings of SPIE - The International Society for Optical Engineering
    ISSN0277-786X

    Keywords

    • Orbital angular momentum of light
    • Fiber mode excitation
    • Gradient descent
    • Spatial light modulator
    • Machine learning

    Fingerprint

    Dive into the research topics of 'SLM phase mask optimization for fiber OAM mode excitation'. Together they form a unique fingerprint.

    Cite this