The relaxation processes of dielectric, modulus and impedance in Dy0.55Sr0.45Mn1- xFexO3. (November 2021)

• Record Type: Journal Article
• Authors: Yadagiri, K.; Nithya, R.
• Is Part Of: Journal of physics and chemistry of solids. Volume 158(2021)
• Publication Date: 2021-11
• Subjects: X-ray diffraction -- Dielectric relaxations -- Modulus -- Variable Range Hopping conduction -- Cole-Cole plot; Solids -- Periodicals; Solides -- Périodiques; Solids; Periodicals; 530.41
• DOI: 10.1016/j.jpcs.2021.110232
• Languages: English
• ISSNs: 0022-3697

Abstract

Abstract: The ac electrical properties of orthorhombic ceramics, Dy0.55 Sr0.45 Mn1-x Fex O3 (x = 0, 0.4 and 1.0) in the range of frequency 0.5–10 7 Hz and temperature 126–299 K have been studied. Across the series, dielectric permittivity and loss increase with increase in Fe concentration. Non-Debye type dielectric relaxation peak was found in x = 0.4 compound among Dy0.55 Sr0.45 Mn1-x Fex O3 materials and consequently activation energy of the dielectric relaxation was calculated. The results of impedance spectroscopy revealed that for higher concentration of Fe in the series, impedance (Z′) is low. The relaxation peaks in impedance, Z″ are observed at different frequency ranges for different Fe concentration in the compounds. From the temperature dependence of these peaks, activation energies are determined. The results of modulus spectra indicated a similar behavior as impedance, but x = 0.4 compound showed a large activation energy among the compounds in the series. Cole-Cole plots displayed negative temperature coefficient of resistance, a normal behavior of semiconductors. These plots also suggested that the dielectric relaxation is of non-Debye type. The scaling behavior in the modulus and impedance suggested that temperature dependence of relaxation processes exists in these materials. These studies and results are significant for materials which exhibit high resistance in low temperature. Highlights: Dy0.55 Sr0.45 Mn1-x Fex O3 - x = 0.4 showed Non-Debye type dielectric relaxation peak, and manipulated the r dielectric relaxation energy. The analysis of dielectric loss, modulus, and impedance spectra showed variable range hopping conduction present in these materials. Scaling behavior of modulus and impedance suggested the temperature dependent relaxations exist in Dy0.55 Sr0.45 Mn1-x Fex O3 .