Raman scattering of plane-wave and twisted light off chiral molecular liquids

authored by: Florian Büscher, Silvia Müllner, Dirk Wulferding, Yu G. Pashkevich, V. Gnezdilov, A. A. Peshkov, A. Surzhykov, Peter Lemmens
Abstract: We present an experimental study of the quasi-elastic Raman scattering (QES) of plane-wave and twisted light by liquid crystals. Depending on their temperature, these crystals can exhibit isotropic, nematic and chiral nematic phases. The question is addressed of how the phase of a crystal and the state of incident light can affect the quasi-elastic energy spectra of the scattered radiation, whose shape is usually described by the combination of Lorentzian and Gaussian components. Special attention is paid to the chiral phase, for which the Raman QES spectrum is dominated by a Lorentzian with reduced linewidth, pointing to diminished disorder and configurational entropy. Moreover, this phase is also known for a regime of iridescence (selective backscattering) which arises when the wavelength of incident light becomes comparable with the chiral pitch length. Detailed measurements, performed in this resonant regime and by employing twisted light, carrying various projections of the orbital angular momentum (OAM), have indicated a low-energy scattering surplus depending on OAM. We argue that this observation might indicate a transfer of angular momentum between light and liquid crystal.
External Organisation(s): Technische Universität Braunschweig
Korea Basic Science Institute
National Academy of Sciences in Ukraine
B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine
National Metrology Institute of Germany (PTB)
Type: Article
Journal: Low temperature physics
Volume: 47
Pages: 959-965
No. of pages: 7
ISSN: 1063-777X
Publication date: 11.2021
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Physics and Astronomy (miscellaneous)
Electronic version(s): https://doi.org/10.1063/10.0006577 (Access: Unknown)

BibTeX

@article{28f3145188cb4133803765d22bf5da06,
title = "Raman scattering of plane-wave and twisted light off chiral molecular liquids",
abstract = "We present an experimental study of the quasi-elastic Raman scattering (QES) of plane-wave and twisted light by liquid crystals. Depending on their temperature, these crystals can exhibit isotropic, nematic and chiral nematic phases. The question is addressed of how the phase of a crystal and the state of incident light can affect the quasi-elastic energy spectra of the scattered radiation, whose shape is usually described by the combination of Lorentzian and Gaussian components. Special attention is paid to the chiral phase, for which the Raman QES spectrum is dominated by a Lorentzian with reduced linewidth, pointing to diminished disorder and configurational entropy. Moreover, this phase is also known for a regime of iridescence (selective backscattering) which arises when the wavelength of incident light becomes comparable with the chiral pitch length. Detailed measurements, performed in this resonant regime and by employing twisted light, carrying various projections of the orbital angular momentum (OAM), have indicated a low-energy scattering surplus depending on OAM. We argue that this observation might indicate a transfer of angular momentum between light and liquid crystal.",
author = "Florian B{\"u}scher and Silvia M{\"u}llner and Dirk Wulferding and Pashkevich, {Yu G.} and V. Gnezdilov and Peshkov, {A. A.} and A. Surzhykov and Peter Lemmens",
note = "Funding information: We acknowledge important discussions with W. L{\"o}ffler (Univ. Leiden) and G. Napoli (Univ. del Salento, Lecce). This research was funded by DFG EXC-2123-390837967 Quantum-Frontiers, DFG Le967/16-1, DFG-RTG 1952/1, and the Quantum-and Nano-Metrology (QUANOMET) initiative of Lower Saxony within project NL-4. D. W. acknowledges support from the Institute for Basic Science (Grant No. IBS-R009-Y3).",
year = "2021",
month = nov,
doi = "10.1063/10.0006577",
language = "English",
volume = "47",
pages = "959--965",
journal = "Low temperature physics",
issn = "1063-777X",
publisher = "American Institute of Physics",
number = "11",
}