Effect of cobalt on structural, magnetic and magnetocaloric properties of La0.8Ba0.1Ca0.1Mn1-xCoxO3 (x = 0.00, 0.05 and 0.10) manganites

Correlation between magnetic and electric properties based on the critical behavior of resistivity and percolation model of La0.8Ba0.1Ca0.1MnO3 polycrystalline

“…Taking the sign of the temperature derivative of dr/dT as a criterion, we found that samples exhibit a metallic behavior dr/dT > 0 at a low temperature (T < T M-SC ) and become semiconductor like dr/dT above the temperature T M-SC , where T M-SC is the temperature of the maximum value of resistivity. The transition temperature T M-SC occurs at T M-SC ¼ 303 K, which is close to its T C ¼ 282 K, 20 indicating strong correlations between the magnetic and electrical properties in our sample. Therefore, we can dene the FM-metallic-like and the PM-semiconductorlike behaviors as a function of temperature.…”

“…The temperature derivative of resistivity normalized with respect to its value at T M-SC , [1/r(T M-SC )dr/dT] against h is shown in Fig. 10 for our sample, and eqns (20) and (21) are tted below and above T M-SC in the same gures. The solid lines passing through the data the are best ts in the two regions.…”

“…The detailed basic physical properties are reported in ref. 20. The crystal structure of the nal product was checked by X-ray diffraction, which conrmed that the sample having a single phase, crystallized in the rhombohedral structure with R 3c space group.…”

“…The crystal structure of the nal product was checked by X-ray diffraction, which conrmed that the sample having a single phase, crystallized in the rhombohedral structure with R 3c space group. 20 In the present study the electrical transport properties r(T) were measured by a standard four-probe method using physical property measurement system (PPMS, Quantum Design).…”

“…By contrast, the experimental estimates of the critical exponents are still controversial including those for short-range Heisenberg interaction, 16,17 the mean-eld values 17,18 and those which cannot be classied into any universality class ever known. 19 Previously, 20 we have investigated in detail the structural, magnetic and MCE of our sample. In this paper, we intend to study the dependence of the electrical resistivity properties as a function of the La 0.8 Ba 0.1 Ca 0.1 MnO 3 , volume fraction, f, which is analyzed in the framework of the percolation theory.…”