Dielectric constant grain size dependence

FIGURE 3.1.3 Grain size dependence of dielectric constant. 

Temperature dependent dielectrics of Nanocrystalline BaTiOa Ceramics. The dielectric properties with different frequencies for nanocrystalline BaTiOs samples are shown in Figure 6. In the temperature (T) spectra of relative dielectric constant (K) all the samples showed a discernible eubie (C) to T transition. In eomparison, the low temperature transitions were much weaker and broader. At smaller grain size 20 nm, they appeared as diffuse humps on a positively sloping background that is part of the low-temperature tail of the C/T transition. In the range of 20-100 nm, the transition temperatures thus determined show a steady decrease for the C/T transition, in contrast to a steady increase for the T/0 transition and for the 0/R transition. However, even the maximum value of K for 20 nm BaTiOs is only about 930 at IkHz, it still exhibits a broadening and... 

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