Magnetic shape memory effect in single crystalline Ni-Mn-Ga foil thinned down to 1μm

Abstract

We report on observation of magnetic-field-induced twin variant reorientation in a thin foil with variable thickness, fabricated from a bulk five-layered Ni49.5Mn28Ga22.5 single crystal. Formation and motion of twinning interfaces in the foil were induced by magnetic fields of 0.6T. The characteristic “labyrinth” magnetic domain structure was fully retained down to 1 μm thickness. Dependence of the characteristic width of magnetic domains on the sample thickness followed a power law with the exponent of 2/3. The reported results indicate that micrometer-scale sized Ni-Mn-Ga devices, fabricated from a bulk, can be actuated by magnetic field.