Stray-Field-Induced Actuation of Free-Standing Magnetic Shape-Memory Films



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Free-standing epitaxial NiMnGa films are used to demonstrate a novel thermal actuation mode. To avoid the high magnetostatic stray-field energy, the easy axis of the martensitic variants is aligned preferentially in-plane. This results in a maximum strain of up to 1.1% without the need for training or an external magnetic field.