authors 
Tkach, A; Vilarinho, PM; Kholkin, AL 
nationality 
International 
journal 
JOURNAL OF APPLIED PHYSICS 
keywords 
STRONTIUMTITANATE CERAMICS; SOFT PHONON MODES; SRTIO3; FERROELECTRICITY; SR1XCAXTIO3; RANDOMNESS; TRANSITION; DEVICES 
abstract 
The dc electricfield dependence of the dielectric constant epsilon(')(E) in Sr1xMnxTiO3 (x=0.0050.02) ceramics is studied in the temperature range from 10 to 125 K, i.e., around the epsilon(')(T) peak temperature Tmax. Results are analyzed using equations derived analytically from the implicit equations of the LandauGinzburgDevonshire (LGD) theory. Corrections due to cluster contribution attributed to the reorientation of randomfieldinduced polar nanometerscale regions turn out to be important, if not decisive, for a reliable description of epsilon(')(E). So, it is found that a combined equation including the Langevintype cluster term, i.e., epsilon(')(L)(E)=(P0L3)L2/(2k(B)T epsilon(0)[cosh((P0LE)E3/2k(B)T)](2)) is the most suited to describe the dc electricfield dependence of the dielectric constant around Tmax. Based on the fitting of the epsilon(')(E) data, the cluster polarization P0 reaches values as high as similar to 0.4 mu C/cm(2) with the cluster size L of 11 +/ 4.5 nm. Thus, the existence in the Sr1xMnxTiO3 system of polar clusters with nanometerscale size is consistent with epsilon(')(E) data and their contribution to the permittivity at E=0 and temperatures close to Tm is estimated to be up to 30%. In addition, besides inducing the peak in epsilon(T), the formation of polar nanoregions is beneficial to the high relative electricfield tunability of the dielectric constant n(r)=[epsilon(')(0)epsilon(')(E)]/epsilon(')(0)similar to 70% as well as high communication quality factor K=[epsilon(')(0)/epsilon(')(E)1](2)/[epsilon(')(0)/epsilon(')(E)tan delta(0)tan delta(E)]similar to 10 000 under 20 kV/cm at 10 kHz. 
publisher 
AMER INST PHYSICS 
issn 
00218979 
year published 
2007 
volume 
101 
issue 
8 
digital object identifier (doi) 
10.1063/1.2717874 
web of science category 
Physics, Applied 
subject category 
Physics 
unique article identifier 
WOS:000246072200115

ciceco authors
impact metrics
journal analysis (jcr 2019):

journal impact factor 
2.286 
5 year journal impact factor 
2.138 
category normalized journal impact factor percentile 
54.87 
dimensions (citation analysis):


altmetrics (social interaction):


