Abstract
Magnetization, specific heat, thermal diffusivity, and magnetocaloric effect were studied in Pr0.7Sr0.3-xCaxMnO3 system (x = 0; 0.1; 0.2; 0.3) in the temperature range of 80–320 K and in a magnetic field of 18 kOe. A correlation was found between the coefficients under study and microscopic characteristics (〈rA〉 – average ionic radius and σ2 – cationic disorder). The decrease in σ2 and 〈rA〉, caused by the substitution of Sr atoms by Ca atoms, causes a weakening of the exchange interactions and a decrease in ТС. The observed minima in the temperature dependence of thermal diffusivity η(T) near ТС are associated with the appearance of an additional channel of phonon relaxation in fluctuations of the magnetic order parameter. A relationship was found between the MCE value and the change in thermal diffusivity in a magnetic field near ТС. This relationship can be applied as another MCE evaluating indirect method. It is shown that MCE value estimation from thermal diffusivity data is consistent with the results of caloric measurements.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
