Magnetic properties and magnetocaloric effect of Gd element under first order phase transition

Document Type : Original Article

Authors

1 Department of physics, faculty of science, Damietta university, Damietta, Egypt

2 Department of Physics, Damietta University, New Damietta, Egypt

3 Department of Physics, Helwan University, Helwan, Egypt

Abstract

The Bean-Rodbell model is used to study the temperature and field dependences of the magnetization M, magnetic entropy Sm, total entropy Stotal and magnetic specific heat Cm in case of first - order phase transition in the elemental Gd system. For magnetic fields ≤ 5 T and temperature range up to 400 K, the isothermal entropy change ΔSm and the adiabatic temperature change ΔTad are determined. For a magnetic field change of 5 T, the maximum values of ΔSm and ΔTad are 4.599 J/mol. K and 20.1 K, respectively. As the magnetic field changes, the value of the Curie temperature Tc changes slightly. In contrast to the second- order phase transition, the maximum values of the magnetocaloric effect (MCE) for first order transition are larger. The temperature and field dependences of the magnetization, magnetic heat capacity, entropy, ΔSm and ΔTad, in addition to Arrott-plots are indicative of first - order phase transition (FOPT).

Keywords

Main Subjects

Journal of the Egyptian Society for Basic Sciences-Physics
Volume 1, Issue 2 - Serial Number 6
review, original articles, regular articles and Letters to the Editorial Board
July 2024
Pages 57-65

Files

Share

How to cite

Statistics