Magnetically Anisotropic Ni2MnGa Thin Films: Coating Glass and Si Micro-Cantilevers Substrates

Abstract

Ni2MnGa thin films, with thickness between 30 and 60 nm, were pulsed-laser deposited at room temperature on Si micro-cantilevers and glass substrates. Two different deposition processes were performed: normal deposition and off¬-normal. After annealing in an inert atmosphere, in-plane isotropic magnetic hysteresis loops were measured for the normal deposited films. In contrast, in-plane anisotropic hysteresis loops were obtained from the off-normal deposited ones. An in-plane easy direction for the magnetisation, perpendicular to the incidence plane of the plasma during deposition, was measured with an anisotropy field of ≈100 Oe and an easy coercive field of ≈24 Oe. The mechanical behaviour of the magnetically anisotropic coated micro-cantilevers and their response to a decreasing temperature permitted observing the martensitic transformation of the Ni2MnGa thin films.