Low Spontaneous Brillouin Scattering in Anti-Resonant Hollow-Core Fibers in GHz Frequency Range

Ryan E. Dunagin; Robbie Mears; Dario Bueno-Baques; Vasyl S. Tyberkevych; Yi Li; William J. Wadsworth; Zbigniew Celinski; Valentine Novosad; Dmytro A. Bozhko

arXiv · 2506.00287

Low Spontaneous Brillouin Scattering in Anti-Resonant Hollow-Core Fibers in GHz Frequency Range

Ryan E. Dunagin·Robbie Mears·Dario Bueno-Baques·Vasyl S. Tyberkevych·Yi Li·William J. Wadsworth·Zbigniew Celinski·Valentine Novosad·Dmytro A. Bozhko

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Abstract

Brillouin light scattering (BLS) is a powerful experimental tool that can be used to get insights into the fundamental and applied properties of matter, like dispersions of quasiparticles in a solid, as well as their spatio-temporal dynamics. Many applications of light scattering favor the use of optical fibers in place of free-space optics. In this work, we compare the performance of anti-resonant hollow core fibers to that of conventional solid core fused silica fibers for BLS experiments in the GHz frequency range. Conventional fibers are barely suitable for low-noise measurements because of the spontaneous scattering of the photons on various phononic modes present in the core and cladding. In the case of the hollow-core fiber, we identify a range of discrete phononic modes and associate them with the various acoustic modes of the structure surrounding the hollow core using finite-element numerical simulations. The measured relative intensity of the spontaneous BLS signal from these modes is orders of magnitude smaller than that of a solid-core fiber, making anti-resonant hollow-core fibers one of the best solutions for the single-mode light guidance for BLS and potentially other low-noise photonic experiments.

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Ryan E. Dunagin, Robbie Mears, Dario Bueno-Baques, Vasyl S. Tyberkevych, Yi Li, William J. Wadsworth, Zbigniew Celinski, Valentine Novosad, Dmytro A. Bozhko. 2025-05-30. Low Spontaneous Brillouin Scattering in Anti-Resonant Hollow-Core Fibers in GHz Frequency Range. https://arxiv.org/abs/2506.00287

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