Optical and dielectric properties of silver-substituted ZnAl₂O₄ spinels synthesized using a sol-gel auto-combustion method

Abstract

The present study deals with two compounds, (x = 0.05 and x = 0.1), synthesized using a sol-gel auto-combustion method.

Study of physical properties of the Li0.5MgFe1.5O3.5 ferrite nanoparticles

“…Such a relaxation phenomenon is likely to be explained by the presence of electrons and/or immobile species at low temperature and defects at high temperature. 61 Moreover, the increase in the frequency of relaxation peaks with the increase in temperature proves a non-Debye type relaxation, 62 described by Arrhenius' law: 63,64 where K B is the Boltzmann constant, f 0 pre-exponential term, and E a activation energy.…”

“…Moreover, this behavior shows the dominance of the thermally activated jump process, which has been reported in several research investigations. 1,64…”

“…Moreover, this behavior shows the dominance of the thermally activated jump process, which has been reported in several research investigations. 1,64 In order to estimate the activation energy for the studied compound Li 0.5 MgFe 1.5 O 3.5 , we have plotted in Fig. 6(c) the logarithmic variation of the relaxation frequency (f max ) as a function of the inverse of the temperature 1000/T (K), from the data of the imaginary part of the modulus (M ′′ ).…”

Research on the physical properties of LiMn0.5Fe2O4 spinel ferrites by the combination of optical, magnetic, and dielectric behaviors

“…A new method was suggested by Scaife 68 to investigate the dielectric response of the sample. It is based on the substitution of the complex permittivity by the polarizability according to the relation: 69 α * = α ′ − i α ′′ where the imaginary part α ′′ can be easily obtained as follows: …”

“…The quantitative loss of energy (the dielectric loss tangent) in an assorted dielectric material is generally caused by different physical processes, for example, electrical conduction, or dielectric relaxation. 69 Fig. 13 exhibits the temperature-dependent loss tangent (tan θ ).…”