Low-temperature microwave and THz dielectric response in novel microwave ceramics

Low frequency dielectric response of charge density wave systems K0.3MoO3 and o-TaS3 shows hysteresis on temperature cycling. The closing of the hysteresis at low temperature coincides in both systems with the closing of the hysteresis in DC conductivity and corresponds to the temperature of the glass transition observed in dielectric response of these two systems. AC conducitivity is higher on heating, while DC conductivity is lower, i.e. two loops have opposite directions. Higher AC conducitivity (or dielectric response) is a consequence of more corrugated CDW phase on heating.

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Low-temperature dielectric response of NaTaO3 ceramics and films

Applied Physics Letters ◽

10.1063/1.4714527 ◽

2012 ◽

Vol 100 (19) ◽

pp. 192909 ◽

Cited By ~ 19

Author(s):

A. Tkach ◽

A. Almeida ◽

J. Agostinho Moreira ◽

J. Perez de la Cruz ◽

Y. Romaguera-Barcelay ◽

...

Keyword(s):

Low Temperature ◽

Dielectric Response

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Low temperature sintering and dielectric properties of Ba3(VO4)2 microwave ceramics using Co2O3 additives

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-017-7794-5 ◽

2017 ◽

Vol 28 (24) ◽

pp. 18474-18479 ◽

Cited By ~ 3

Author(s):

Zhiyuan Zhang ◽

Haikui Zhu ◽

Yaoyao Li ◽

Long Li ◽

Zhenxiao Fu ◽

...

Keyword(s):

Dielectric Properties ◽

Low Temperature ◽

Low Temperature Sintering ◽

Microwave Ceramics

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Infrared reflectivity and intrinsic dielectric behavior of RETiTaO6 (RE = Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, and Yb) microwave ceramics

Journal of Materials Research ◽

10.1557/jmr.2005.0163 ◽

2005 ◽

Vol 20 (5) ◽

pp. 1164-1171 ◽

Cited By ~ 9

Author(s):

C.W.A. Paschoal ◽

R.L. Moreira ◽

K.P. Surendran ◽

M.T. Sebastian

Keyword(s):

Rare Earth ◽

Dielectric Response ◽

Dielectric Behavior ◽

Quantum Model ◽

Quality Factors ◽

Microwave Ceramics ◽

Phonon Modes ◽

Infrared Reflectivity ◽

Ion Substitution ◽

Dielectric Ceramics

In this work, we performed infrared reflectivity measurements of RETiTaO6 dielectric ceramics for rare-earth (RE) = Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, and Yb. The infrared spectra were analyzed through the four-parameter semi-quantum model based on two orthorhombic (aeschynite and euxenite) structures presented by the ceramics. We discerned the strongest phonon modes that contribute to the intrinsic dielectric behavior of the two families. Then the unloaded quality factors and the dielectric permittivities were estimated at the microwave region. The variations of the intrinsic dielectric response of both systems with RE ion substitution are discussed in terms of changes in their dielectric polarizabilities. It is proposed that the covalency of the RE–O bonds play an important role in the evolution of dielectric permittivity as well as in the sign of the temperature coefficient of the resonant frequency.

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