Non-linear media in weakly curved spacetime

optical solitons and probe pulses for gravimetry

authored by: Alessio Belenchia, Felix Spengler, Dennis Rätzel, Daniel Braun
Abstract: That light propagating in a gravitational field gets frequency-shifted is one of the basic consequences of any metric theory of gravity rooted in the equivalence principle. At the same time, also a time dependent material’s refractive index can frequency-shift light propagating in it. The mathematical analogy between the two effects is such that the latter has been used to study the optical analogue of a black-hole spacetime. Here, we combine these two effects by showing that light propagation in non-linear media in the presence of a moving refractive index perturbation can lead to a gravity-dependent blueshift. We find that the predicted blueshift surpasses the gravitational redshift even if the medium is considered to be perfectly stiff. In realistic scenarios, by far the strongest frequency shift arises due to the deformation of the dielectric medium and the corresponding photoelastic change of refractive index. This has the potential to facilitate optical sensing of small gravity gradients.
External Organisation(s): University of Tübingen
Queen's University Belfast
Center of Applied Space Technology and Microgravity (ZARM)
Type: Article
Journal: New journal of physics
Volume: 26
ISSN: 1367-2630
Publication date: 12.08.2024
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Physics and Astronomy(all)
Electronic version(s): https://doi.org/10.1088/1367-2630/ad678d (Access: Open)

BibTeX

@article{9ee2e9cd7f604ed19d1c2f2d808378fb,
title = "Non-linear media in weakly curved spacetime: optical solitons and probe pulses for gravimetry",
abstract = "That light propagating in a gravitational field gets frequency-shifted is one of the basic consequences of any metric theory of gravity rooted in the equivalence principle. At the same time, also a time dependent material{\textquoteright}s refractive index can frequency-shift light propagating in it. The mathematical analogy between the two effects is such that the latter has been used to study the optical analogue of a black-hole spacetime. Here, we combine these two effects by showing that light propagation in non-linear media in the presence of a moving refractive index perturbation can lead to a gravity-dependent blueshift. We find that the predicted blueshift surpasses the gravitational redshift even if the medium is considered to be perfectly stiff. In realistic scenarios, by far the strongest frequency shift arises due to the deformation of the dielectric medium and the corresponding photoelastic change of refractive index. This has the potential to facilitate optical sensing of small gravity gradients.",
keywords = "analog gravity, curved spacetime, gravimetry, non-linear media, optical solitons",
author = "Alessio Belenchia and Felix Spengler and Dennis R{\"a}tzel and Daniel Braun",
note = "Publisher Copyright: {\textcopyright} 2024 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft.",
year = "2024",
month = aug,
day = "12",
doi = "10.1088/1367-2630/ad678d",
language = "English",
volume = "26",
journal = "New journal of physics",
issn = "1367-2630",
publisher = "IOP Publishing Ltd.",
number = "8",
}