Calculation of the H-T phase diagram, magnetization and susceptibility in layered structures

Date

2015-11-01

Author

Yurtseven, Hasan Hamit
Emre, B.
Acet, M.

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The magnetic Field-temperature (H-T) phase diagram is calculated using the mean held theory by expanding the free energy in terms of the uniform and staggered magnetization for the ferromagnetic-antiferromagnetic transitions in the La0.6Nd0.4Mn2Si2 multilayer structures. Using our experimental measurements, analysis of the magnetization as a function of the magnetic held at constant temperatures from 45 K to 250 K is performed by a power-law formula close to the ferromagnetic-antiferromagnetic transitions. Also, by obtaining the magnetic field dependence of the isothermal susceptibility chi(T) from the M-H curves, chi(T) vs. H-H-c, is analyzed (H-c is the critical magnetic field) using a powerlaw formula for the antiferromagnetic-ferromagnetic (AF-FM) transitions in La0.6Nd0.4Mn2Si2. It is found that a discontinuous (first order) transition which occurs at the lowest (45 K) and the highest (250 K) temperatures, changes to a continuous one at a constant temperature at around 100 K as the magnetic Field carries the systems from the antiferromagnetic to the ferromagnetic phase. Values of the critical exponents associated with this transition are deduced and they are compared with the predictions of some theoretical models.

Subject Keywords

H-T phase diagram, Magnetization, Isothermal susceptibility, AF-FM transition, Multilayer structures, Mean field theory

URI

https://hdl.handle.net/11511/48317

Journal

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

DOI

https://doi.org/10.1016/j.jmmm.2015.06.026

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, B. Emre, and M. Acet, “Calculation of the H-T phase diagram, magnetization and susceptibility in layered structures,” JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, pp. 544–550, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/48317.