Magnetocaloric-Transport Properties Correlation in La0.8 Ca0.2MnO3-Doped Manganites

Abstract

This investigation is interested in studying the relation between magnetocaloric effect and transport properties i La 0.8 Ca 0.2 MnO 3 manganite compound. The value of the magnetocaloric effect has been determined from the calculation of magnetization as a function of temperature under different external magnetic fields. This study also provides an alternative method to determine the magnetocaloric properties such as magnetic entropy change and heat capacity change on the basis of M(T , H ) measurements. On the other hand, based on magnetic and resistivity measurements, the magnetocaloric properties of this compound were investigated using an equation of the formδT H dH , which relates magnetic order to transport behavior of the compounds. As an important result, the values of MCE and the results of calculation are in good agreement with the experimental ones, which indicates the strong correlation between the electric and magnetic properties in manganites.

Investigation on structural, magneto-transport, magnetic and thermal properties of La0.8Ca0.2−xBaxMnO3 (0⩽x⩽0.2) manganites

“…We have estimated the Curie temperatures, of the samples from the inflection point of dM/dT versus plots and are shown in the insets. The pristine sample exhibits T C value of about 197 K which is much less than that reported for similar compound by Skini et al [12]. We can explain the reason for this variation in T C values.…”

“…In particular La 1-x Ca x MnO 3 (LCMO) compounds have attracted extra attention because of occurrence of enormous magneto-resistance (MR) and huge magneto-caloric effect (MCE) which makes them good candidates for applications [5][6][7][8][9][10][11][12][13][14][15].…”

Effect of Ba substitution on structural, electrical and thermal properties of La0.65Ca0.35−Ba MnO3 (0 ⩽x⩽ 0.25) manganites

“…Rostamnejadi et al [10] have shown that La 0.67 Sr 0.33 MnO 3 manganites are ideal candidates for magnetic refrigeration above room temperature at moderate magnetic fields. In particular, La 1Àx Ca x MnO 3 compounds are important as they have the largest CMR effect, attributed to the presence of an electronic phase separation between hole-poor anti-ferromagnetic regions and hole-rich ferromagnetic regions [11][12][13][14]. Skini et al [13] has shown that lanthanum deficient manganites have MCE and RCP values close to gadolinium.…”

“…In particular, La 1Àx Ca x MnO 3 compounds are important as they have the largest CMR effect, attributed to the presence of an electronic phase separation between hole-poor anti-ferromagnetic regions and hole-rich ferromagnetic regions [11][12][13][14]. Skini et al [13] has shown that lanthanum deficient manganites have MCE and RCP values close to gadolinium. Lee et al [14] have demonstrated that sintering temperature plays an important role on MCE and RCP.…”

Magnetocaloric effect of perovskite manganites La0.7□0.1Ca0.2MnO3

“…(1) and (2), the entropy changes determined by the resistivity measurement and the Maxwell relation, described in our previous research work [7], are shown in Fig. 3.…”