CRITICAL DIELECTRIC-RELAXATION IN FERROELECTRIC BETAINE PHOSPHITE IN THE MICROWAVE REGION

Authors
SOBIESTIANSKAS R GRIGAS J CZAPLA Z DACKO S
Citation
R. Sobiestianskas et al., CRITICAL DIELECTRIC-RELAXATION IN FERROELECTRIC BETAINE PHOSPHITE IN THE MICROWAVE REGION, Physica status solidi. a, Applied research, 136(1), 1993, pp. 223-228
Citations number
16
Journal title
Physica status solidi. a, Applied research → ACNP
ISSN journal
00318965
Volume
136
Issue
1
Year of publication
1993
Pages
223 - 228
Database
ISI
SICI code
0031-8965(1993)136:1<223:CDIFBP>2.0.ZU;2-R
Abstract
The dielectric behaviour of ferroelectric hydrogen-bonded betaine phos phite crystals is investigated in the frequency range up to 77 GHz. Th e dielectric dynamics of Debye-type shows a critical slowing-down of t he polarization fluctuations. The frequency of the relaxational soft m ode in the paraelectric phase varies according to v(s) = 0.36(T-218) G Hz and decreases to 2.4 GHz at T(C) = 224 K. The calculated activation energy for flipping proton motion DELTAU = 2.7kT(C) shows the order d isorder character of the proper ferroelectric phase transition.