Lattice dynamics and broad-band dielectric properties of the KTaO3 ceramics

2012 ◽  
Vol 111 (10) ◽  
pp. 104101 ◽  
Author(s):  
Sebastjan Glinšek ◽  
Dmitry Nuzhnyy ◽  
Jan Petzelt ◽  
Barbara Malič ◽  
Stanislav Kamba ◽  
...  
2015 ◽  
Vol 117 (8) ◽  
pp. 084101 ◽  
Author(s):  
R. Mackeviciute ◽  
V. Goian ◽  
S. Greicius ◽  
R. Grigalaitis ◽  
D. Nuzhnyy ◽  
...  

1994 ◽  
Vol 50 (18) ◽  
pp. 13379-13387 ◽  
Author(s):  
Changyol Lee ◽  
Philippe Ghosez ◽  
Xavier Gonze

2018 ◽  
Vol 113 ◽  
pp. 82-85 ◽  
Author(s):  
Ahmad Alsaad ◽  
Chris M. Marin ◽  
Nabil Alaqtash ◽  
Hsien-Wen Chao ◽  
Tsun-Hsu Chang ◽  
...  

2015 ◽  
Vol 57 (4) ◽  
pp. 675-682 ◽  
Author(s):  
M. S. Pavlovskii ◽  
A. S. Shinkorenko ◽  
V. I. Zinenko

2002 ◽  
Vol 66 (15) ◽  
Author(s):  
Masayoshi Mikami ◽  
Shinichiro Nakamura ◽  
Osamu Kitao ◽  
Hironori Arakawa

2021 ◽  
Author(s):  
Pallabi Gogoi ◽  
Pramila Rani PNVVL ◽  
K A Emmanuel ◽  
L Robindro Singh ◽  
Pamu D

Abstract Oxide thin films attracted significant attention because of their favorable responses, especially dielectric and stable electrical properties. In this study, nanocrystalline (Mg0.95Zn0.05)TiO3 (MZT) films are deposited on Pt/TiO2/SiO2/Si and quartz substrates by radio-frequency (RF) reactive magnetron sputtering. The effect of deposition gas ratio, i.e., the proportion of oxygen and argon (O2/Ar) on broad band and microwave dielectric properties and impedance spectroscopy of MZT films are investigated. The dielectric properties showed a wide range of variation with the different O2/Ar ratios. The MZT film deposited in a pure oxygen environment showed the best dielectric properties, and the plasma survived which shows that the target is not fully oxidized. The impedance spectroscopy of the film deposited under a pure oxygen environment exhibited the single semi-circular arc. The Ag/ MZT/Pt thin films capacitors exhibited the best dielectric constant with low loss tangent. The microwave dielectric constant measured at different spot frequencies in the GHz range displayed inferior dielectric response as compared to their bulk counterparts. An equivalent circuit model to explain the Nyquist plots of MZT films are worked out. The observed electrical and dielectric characteristics of the thin films suggest interesting applications in dielectric mirror and integrated circuits.


1997 ◽  
Vol 500 ◽  
Author(s):  
G. P. Sinha ◽  
B. Batalla ◽  
F. M. Aliev

ABSTRACTWe applied ultra broad-band dielectric spectroscopy in the frequency range from 10–3 Hz to 109 Hz to investigate the effect of size, shape and volume fraction of the pores in the porous matrices on the dielectric properties of liquid crystals (LC) dispersed in these matrices. Measurements in such a broad frequency range make it possible to obtain detailed information on the important aspects of the electrical behavior of heterogeneous materials such as: conductivity, surface polarization, and influence of confinement on dynamics of molecular motion of polar molecules forming LC. We investigated alkylcyanobiphenyls in the isotropie, nematic and smectic phases dispersed in porous glasses (average pore sizes - 100 Å and 1000 Å) which have randomly oriented, interconnected pores, and anopore membranes (pore diameters - 200 Å and 2000 Å) with parallel cylindrical pores. Dispersion of LC resulted in qualitative changes of their dielectric properties. Analysis of broad-band dielectric spectra shows that in organic (LC) - inorganic (porous matrix) heterogeneous composites conductivity plays an important role at F <1 Hz. We observe the appearance of new dielectric modes: a very slow process with characteristic frequency ≃ (1 – 10) Hz and a second process in frequency range about (103 - 106) Hz. The slow process arises due to the relaxation of interfacial polarization at pore wall - LC interface. The origin of this could be due to absorption of ions at the interface. Another possibility is the preferential orientation of the permanent dipoles at pore surface. The second new mode is due to the hindered rotation of the molecules near the interface. Additionally we observed two bulk like modes due to the rotation of the molecules around their short and long axii which are modified.


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