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Polycrystalline Ni-Mn-Ga thin films have been deposited by the pulsed laser deposition ͑PLD͒ technique, using slices of a Ni-Mn-Ga single crystal as targets and onto Si ͑100͒ substrates at temperatures ranging from 673 K up to 973 K. Off-stoichiometry thin films were deposited at a base pressure of 1ϫ10 Ϫ6 Torr or in a 5 mTorr Ar atmosphere. Samples deposited in vacuum and temperatures above 823 K are magnetic at room temperature and show the austenitic ͕220͖ reflection in their x-ray diffraction patterns. The temperature dependences of both electrical resistance and magnetic susceptibility suggest that these samples exhibit a structural martensitic transition at around 260 K. The magnetoresistance ratio at low temperature can be as high as 1.3%, suggesting the existence of a granular structure in the films.

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Magnetic-field-induced strain in single crystals of Ni-Mn-Ga magnetic shape memory alloys were studied under cyclic field conditions using a compression spring to reset the sample as H -f 0. Low frequency actuation strain of 2.5% degraded to about 1.5% at an actuation frequency of 500 Hz. Two resonant-like features appear in the (f data, which appear to correspond to a broad test system resonance (100 -200 Hz) and a sample longitudinal resonance near 350 Hz. The relative phase of field and strain support the assignment of the 350 Hz resonance to the sample.

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The effective anisotropy field and the saturation magnetostriction constant are presented as a function of the annealing parameters for Fe93−x−yZr7BxCuy (x = 6, 8 and y = 0, 1, 2) samples. The results obtained for these magnetic properties are interpreted in terms of microstructure–magnetization interactions, which lead to an enhancement of the soft magnetic character in the samples. Experimental data on saturation magnetostriction are analysed from the point of view of the surface properties and the magnetostriction constant, which describes the interface between the crystalline grain and the amorphous matrix.