0000000000675923
AUTHOR
Luu Thi Nhan
showing 6 related works from this author
Effects of illumination on the dielectric response of barium-strontium niobate ceramics
2013
A study of the effects of white light on the low and infra-low frequency relaxation of polarization in the barium-strontium niobate (SBN) ceramics is reported. The light is found considerably decreasing the contribution of space charge at temperatures corresponding to the range of the relaxor phase (it is, around the Tm).
Photoelectric Current and Dielectric Properties of Barium-Strontium Niobate Ceramics under UV and Visible Irradiation
2015
A study of photocurrent kinetics and dielectric response to infra-low frequencies in the range of the broad phase transition in the Ba0.25Sr0.75Nb2O6 (BSN-75) relaxor ceramics under visible and ultraviolet radiation is reported. Anomalies are revealed in the dependence on field intensity of dielectric permittivity and dielectric loss determined from measurements of polarisation loops before and after illumination. The effects of pyro-electric space charge, polarisation and photovoltaic contributions on behaviour of the measured photocurrent are discussed. Results of the kinetics of photocurrent and dielectric response to infra-low frequency studied at different temperatures are discussed as…
Relaxor Properties of Barium-Strontium Niobate Ceramics
2011
Dielectric properties of Sr0.75Ba0.25Nb2O6 (SBN-75) ceramics in the range of low and infra-low frequencies are reported. The values of ϵ′ and, in particular of ϵ″, in ceramics are found to be much smaller compared with SBN-75 single crystals below the temperature (Тm) of the ϵ′(T) maximum a sharp increase of the values of dielectric parameters observed above Тm being also different from their thermal behaviour in single crystals. The broadening of phase transition and dependence of the response on sample history are similar to the features observed in other relaxor materials.
Kinetics of dielectric response in SBN-75 ceramics at infra-low frequencies under illumination
2014
A study of the photo-dielectric effect in ferroelectric SBN-75 ceramics of a broad phase transition under light of small intensity is reported. Relations determining kinetics of the infra-low frequency dielectric response under light and after illumination are obtained from experimental measurements revealing the features of the behaviour of relaxation time constants of the dielectric polarisation with temperature.
Relaxation of Polarization at the Broad Phase Transition in Modified PMN Ferroelectric Ceramics
2013
The reported study is focused on effects of relaxation of polarization within the range of the broad phase transition at strong sinusoidal measuring fields in modified lead magnesium niobate ceramics. The obtained results reveal an essential thermal broadening of the ϵ′(E) spectra specific to relaxor ferroelectrics. Temperature dependence of ϵ′ eff (T) at medium fields shows two broad maximums – at Tm and at 40°C. On the basis of analysis of the experimental data, admixture of lithium is suggested to promote formation of domains in lead magnesium niobate ceramics.
Photoelectrical Properties of the SBN Relaxor Ceramics in the Range of the Broad Phase Transition
2014
AbstractA study of the effects of white light on photocurrent kinetics and the low and infra-low frequency relaxation of polarization in the barium-strontium niobate SBN‑75 ceramics is reported. It is found that at a low intensity illumination in the range of the relaxor phase the space charge is mainly responsible for manifestation of photo-electrical properties of SBN-75 ceramics.