First order magneto-structural transition and magnetocaloric effect in MnNiGe$_{0.9}$Ga$_{0.1}$

Pallab Bag; R. Nath

doi:10.1016/j.ssc.2017.11.012

paper

First order magneto-structural transition and magnetocaloric effect in MnNiGe $_{0.9}$ Ga $_{0.1}$

arXiv:1706.04740 · doi:10.1016/j.ssc.2017.11.012

Abstract

The first order magneto-structural transition ( $T_{t} ≃ 95$ K) and magnetocaloric effect in MnNiGe $_{0.9}$ Ga $_{0.1}$ are studied via powder x-ray diffraction and magnetization measurements. Temperature dependent x-ray diffraction measurements reveal that the magneto-structural transition remains incomplete down to 23 K, resulting in a coexistence of antiferromagnetic and ferromagnetic phases at low temperatures. The fraction of the high temperature Ni $_{2}$ In-type hexagonal ferromagnetic and low temperature TiNiSi-type orthorhombic antiferromagnetic phases is estimated to be $\sim 40%$ and $\sim 60%$ , respectively at 23 K. The ferromagnetic phase fraction increases with increasing field which is found to be in non-equilibrium state and gives rise to a weak re-entrant transition while warming under field-cooled condition. It shows a large inverse magnetocaloric effect across the magneto-structural transition and a conventional magnetocaloric effect across the second order paramagnetic to ferromagnetic transition. The relative cooling power which characterizes the performance of a magnetic refrigerant material is found to be reasonably high compared to the other reported magnetocaloric alloys.

arXiv comment6 pages, 4 figures

First order magneto-structural transition and magnetocaloric effect in MnNiGe0.9​Ga0.1​

Abstract

References in corpus (11)

First order magneto-structural transition and magnetocaloric effect in MnNiGe $_{0.9}$ Ga $_{0.1}$