Rapid floating zone growth of Ni2MnGa single crystals exhibiting magnetic shape memory functionality

Abstract

To obtain a material exhibiting magnetically induced reorientation (MIR), one of the magnetic shape memory effects, a well-developed method for single crystal growth is crucial. A [100] oriented Ni2MnGa single crystal exhibiting MIR was successfully prepared using the floating-zone technique with a high speed of 80 mm/h. The comparison with a sample grown by Bridgman method and a reference sample grown in AdaptaMat Ltd. by directional solidification is provided based on elemental homogeneity, crystallographic quality by x-ray diffraction, transformation behaviour and magnetic properties. All these methods indicated that the single crystal grown by floating zone with high speed is comparable or superior to the samples prepared by other methods. Importantly, the magnetization measurement revealed that the single crystal prepared this way exhibits MIR down to 10 K.