Heusler‐Based Cylindrical Micro‐ and Nanowires
Miroslav Hennel, M. Varga, L. S. Frolova, Samuel Nalevanko, P. J. Ibarra-Gaytán, R. Vidyasagar, Partha Sarkar, Andrea Džubinská, Ladislav Galdun, T. Ryba, Zuzana Vargová, R. Varga
Abstract
Wire‐shaped materials are ideal form for rapid, cheap, and scalable production and application. Herein, the most recent results on Heusler‐based cylindrical micro‐ and nanowires are reviewed, emphasizing spintronic, magnetocaloric, and shape memory applications. Herein, how the Heusler alloy's composition can be tuned to achieve a material with repeatable magnetic and mechanical properties is showed. A wide range of possible Heusler compositions allows us to tune the structural transformation temperatures by alloying the original composition with a few percent of metalloid. Wire shape brings additional effect—well‐defined easy axis change due to a structural transformation that enhances the magnetocaloric effect at low‐magnetic fields. The unique wire's shape properties can be downscaled to nanoscale range by electrodeposition. It is showed that such a method allows the production of a highly ordered array of nanowires. As a result, the magnetocaloric effect of an array of nanowires can be one order higher than that obtained by other production methods, where the nanowires are oriented randomly. Finally, some possible applications of shape memory or magnetocaloric actuators and the possibility of implementing high spin polarization for the construction of spintronic devices are showed.