Domain glass dynamics of potassium thiocyanate (KSCN)

Autor(en)

V. Soprunyuk, P. König, A. Tröster, W. Schranz, M. A. Carpenter, E. K.H. Salje

Abstrakt

We study the dynamic elastic behavior of potassium thiocyanate (KSCN) in the temperature region of the order-disorder improper ferroelastic phase transition using dynamic mechanical analysis (0.05-40 Hz) and resonance ultrasound spectroscopy (100-600 kHz). The low frequency data show—in addition to the intrinsic phase transition anomalies—softening in a- and b-directions below T c , which results from movements of ferroelastic domain walls under dynamic stress. In contrast to many other ferroelastic materials (LaAlO 3 , PbZrO 3 , SrTiO 3 , etc.), the domain wall motion in KSCN freezes already at a temperature below T c -20 K. The corresponding increase of the domain wall relaxation time τ D W with decreasing temperature can be well fitted by a Vogel-Fulcher law τ D W = τ 0 exp [ E a / k B ( T − T VF ) ] with τ 0 ≈ 10 − 7 s, E a ≈ 0.035 eV, and T V F ≈ 368 K, indicating domain glass behavior. The high frequency elastic moduli ( ∼ f 2 ) (100-600 kHz) do not show any precursor softening with decreasing temperature due to the large order parameter relaxation time τ η . In contrast to the high frequency elastic moduli, the corresponding losses Q − 1 exhibit peaks at T c = 415 K, which may be explained by order parameter fluctuations.

Organisation(en)

Physik Funktioneller Materialien, Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

Technische Universität Wien, University of Cambridge

Journal

Journal of Applied Physics

Band

137

Anzahl der Seiten

11

ISSN

0021-8979

DOI

https://doi.org/10.1063/5.0263285

Publikationsdatum

04-2025

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik, 104011 Materialchemie

ASJC Scopus Sachgebiete

Allgemeine Physik und Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/ff6aae8b-de33-441f-8549-a4ed74d60413