Correlation of the magnetocaloric effect and magnetostriction near the first-order phase transition in Pr0.7Sr0.2Ca0.1MnO3 manganite

Abstract

Results of the experimental investigations of magnetocaloric effect (MCE) and magnetostriction in Pr0.7Sr0.2Ca0.1MnO3 manganite in the temperature range of 80–310 K and in magnetic fields up to 80 kOe are presented. The behavior of the MCE is characteristic of materials with magnetostructural phase transitions of the first order. Frequency (1–14 Hz) dependences of the MCE in a magnetic field of 6.2 kOe are investigated. It is shown that near TC, the ΔT dependence of the frequency f is well described by the expression: ΔT(f)=ΔTf=0−Bfn (n = 1.53, B = 0.01185 K/Hzn). The results of the investigation of magnetostriction show that near TC, the value of magnetostriction is Δɛ = 4.49 ⋅ 10−4 in a magnetic field of 80 kOe. According to the results of the study of magnetostriction in various magnetic fields, it is shown that the change in the magnetic entropy is directly proportional to magnetostriction ΔSM = γ1Δɛ (γ1 = 2 ⋅ 104 J/kg K). This ratio can serve as another indirect method for estimating the MCE, which shows good agreement with the data of direct caloric measurements.