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arXiv · 1809.02400

Bipolar electrocaloric effect in Pb1-xGdx(Mg1+x/3Nb2-x/3)O3 ceramic: relaxor with super-dipolar glass state

Adityanarayan H. Pandey·A. M. Awasthi·Surya Mohan Gupta
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Abstract

The electrocaloric (EC) effect is calculated for Gd-substituted PMN (x = 0 to 0.1) relaxors from temperature dependent heat capacity and polarization measurements, using a thermodynamic Maxwell equation. Polarization change with temperature reveals an anomalous behaviour around the glass transition temperature, which is in the vicinity of a crossover from positive to negative EC effect, which is explained evoking the critical slowing-down of the polar nano-domains dynamics to super-dipolar glass state upon cooling. The maximum negative EC coefficient is observed to decrease from 0.4 K-mm/kV at 164 K to 0.1 K-mm/kV with x.

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Adityanarayan H. Pandey, A. M. Awasthi, Surya Mohan Gupta. 2018-09-07. Bipolar electrocaloric effect in Pb1-xGdx(Mg1+x/3Nb2-x/3)O3 ceramic: relaxor with super-dipolar glass state. https://doi.org/10.1016/j.scriptamat.2018.10.027

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