Study of magnetic properties in materials Ni_1−xCo_xMnGe systems

Abstract

Purpose

The purpose of this paper is to study the magnetic properties of the materials Ni_1−xCo_xMnGe systems by: mean field theory, probability law and high‐temperature series expansions (HTSE) in the range 0≤x≤1. The nearest neighbour J₁(x) and the next‐nearest neighbour super‐exchange interaction J₂(x) are calculated, using the mean field theory and in the range 0≤x≤1.

Design/methodology/approach

The magnetic phase diagrams (T_C versus dilution x) and the critical exponents associated with the magnetic susceptibility (γ) and with the correlation lengths (ν) are deduced for Ni_1−xCo_xMnGe in the ordered phase by HTSE method has combined with the Padé approximants method for the Ni_1−xCo_xMnGe.

Findings

The obtained magnetic phase diagram of Ni_1−xCo_xMnGe systems is comparable with those obtained by experiment. The values of critical exponents are nearest to those of 3D Heisenberg model and insensitive to the dilution.

Originality/value

Besides the magnetic shape memory effect, the magnetocaloric effect, which exhibits in Ni‐Mn‐Ge or Co‐Mn‐Ge alloys, is of technological interest.

Citation

Masrour, R. (2011), "Study of magnetic properties in materials Ni_1−xCo_xMnGe systems", Multidiscipline Modeling in Materials and Structures, Vol. 7 No. 1, pp. 24-28. https://doi.org/10.1108/15736101111141412