Anomalous magnetic properties in Ni₅₀Mn₃₅In₁₅

Abstract

Abstract. We present here a comprehensive investigation of the magnetic ordering in Ni 50 Mn 35 In 15 composition. A concomitant first order martensitic transition and the magnetic ordering occurring in this off-stoichiometric Heusler compound at room temperature signifies the multifunctional character of this magnetic shape memory alloy. Unusual features are observed in the dependence of the magnetization on temperature that can be ascribed to a frustrated magnetic order. It is compelling to ascribe these features to the cluster type description that may arise due to inhomogeneity in the distribution of magnetic atoms. However, evidences are presented from our ac susceptibility, electrical resistivity and dc magnetization studies that there exists a competing ferromagnetic and antiferromagnetic order within crystal structure of this system. We show that excess Mn atoms that substitute the In atoms have a crucial bearing on the magnetic order of this compound. These excess Mn atoms are antiferromagnetically aligned to the other Mn, which explains the peculiar dependence of magnetization on temperature.Submitted to: J. Phys. D: Appl. Phys.

Structural and magnetic properties probed using neutron diffraction technique in Ni50−xCoxMn38Sb12 (x=0 and 5) Heusler system

“…Here the observed bond distance value is close to the reported value in Ni 50 Mn 35 In 15 system, Where Mn-Mn distance at its own site is 4.27 Å and 2.91 Å for the distance between different sites of Mn [29]. For orthorhombic structure the bond distance between Mn-Mn at 2a site is 4.28 Å and 3.95 Å between Mn at 2a and 2f sites.…”

Martensitic transformation and magnetic properties in ferromagnetic shape memory alloy Ni43Mn46Sn11−xSix

“…The final level of ac susceptibility corresponds to the ferromagneticeantiferromagnetic mixed state of the matrix, and the apparent peak at 161 K is related to frustration of magnetization during the Curie transition. Similar ac susceptibility abnormality peak has also been observed in a Ni 50 Mn 35 In 15 alloy [18], due to magnetic heterogeneity of the alloy matrix.…”

Exchange bias behavior in Ni50.0Mn35.5 In14.5 ribbons annealed at different temperatures

“…Nevertheless, the magnitude of the coercive field is too small if there were clusters of FM ordering. Moreover, the virgin curve initially shows a linear rise in magnetization with increasing field up to around 500 Oe and then the slope changes and lies outside of the hysteresis loop suggesting a field-induced transition [19]. All these features clearly demonstrate the complex magnetic behavior of as-spun and annealed Ni 50.0 Mn 35.5 In 14.5 ribbons as result of competing FM/AFM interactions present in the alloy.…”