Unusual set of anomalies in the lattice dynamics of lawsonite near its phase transitions

Kadlec, Filip; Nuzhnyy, Dmitry; Kadlec, Christelle; Petzelt, Jan; Savinov, Maxim; Kamba, Stanislav

doi:https://dx.doi.org/10.1109/IRMMW-THz50927.2022.9895469

Number of the records: 1

Unusual set of anomalies in the lattice dynamics of lawsonite near its phase transitions

1.

SYSNO ASEP	0569211
Document Type	C - Proceedings Paper (int. conf.)
R&D Document Type	Conference Paper
Title	Unusual set of anomalies in the lattice dynamics of lawsonite near its phase transitions
Author(s)	Kadlec, Filip (FZU-D)_{RID, ORCID, SAI} Nuzhnyy, Dmitry (FZU-D)_{RID, ORCID} Kadlec, Christelle (FZU-D)_{RID, ORCID} Petzelt, Jan (FZU-D)_{RID, ORCID, SAI} Savinov, Maxim (FZU-D)_{RID, ORCID} Kamba, Stanislav (FZU-D)_{RID, ORCID, SAI}
Article number	9895469
Source Title	International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) /47./. - New York : IEEE, 2022 - ISSN 2162-2027 - ISBN 978-1-7281-9427-1
Number of pages	2 s.
Publication form	Print - P
Action	International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) /47./
Event date	28.08.2022 - 02.09.2022
VEvent location	Delft
Country	NL - Netherlands
Event type	WRD
Language	eng - English
Country	US - United States
Keywords	lawsonite ; terahertz spectroscopy ; soft mode ; dielectric permittivity
Subject RIV	BM - Solid Matter Physics ; Magnetism
OECD category	Condensed matter physics (including formerly solid state physics, supercond.)
R&D Projects	GA20-01527S GA ČR - Czech Science Foundation (CSF)
Institutional support	FZU-D - RVO:68378271
UT WOS	000865953000004
EID SCOPUS	85139879074
DOI	10.1109/IRMMW-THz50927.2022.9895469
Annotation	Lawsonite is a water-containing mineral occurring in the Earth’s crust and mantle, exhibiting low-temperature ferroelectricity linked to water molecules. Using broad-band polarized electromagnetic spectroscopy, we studied the lattice dynamics of a single crystal between 1Hz and 20THz at temperatures from 20 to 500K. We identified three anomalies associated with the two phase transitions occurring at 270 and 124K—a critical GHz relaxation, a soft THz phonon, and an overdamped sub-THz excitation in the E∥a,E∥b and E∥c permittivity spectra, respectively. The fact that the soft mode is polarized perpendicularly to the ferroelectric axis is very unusual.
Workplace	Institute of Physics
Contact	Kristina Potocká, potocka@fzu.cz, Tel.: 220 318 579
Year of Publishing	2023
Electronic address	https://ieeexplore.ieee.org/document/9895469

Number of the records: 1