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Frequency reference based on acetylene spectroscopy in hollow core fibers and optical phase locks using FPGA based detection and feedback.

Guillaume Baclet

Published Nov 3, 2023• 0 citations

Abstract

AMO experiments have advanced the fields of precision metrology for time and frequency and quantum sensing in the last decades. Laser locked on accurate frequency reference are central to these experiments to adress atomic transition and manipulate the atomic clouds. The prospects that the portability of these experiments can offers have motivated the devellopement of portable frequency reference . In this work, a fibered frequency reference based on hollow-core photonic crystal fibers is presented. The spectrocopy of acetylene gas trapped in the fiber using a modulation transfer spectroscopy is studied and the stability of a frequency lock is characterised. The application of this technique offers numerous benefits such as compactness, robustness, and the capacity for a fully fibered laser system using telecom lasers. This approach aims to enhance portability and robustness in a variety of applications, including satellite navigation, quantum sensing, and telecommunications networks.Additionally, the thesis extends to developing an architecture for an OPLL based on FPGA, applied to Raman beams. A minimal architecture aims to establish low-noise phase lock, enabling cold atom coherent manipulation, using a reduced amount of components while offering the versatility of a digitally design phase lock loop.

DOI: 10.70675/bfb552adzb878z48a6zb726z0c786807e143

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