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arXiv · 1602.09064

Strong reduction of the coercivity by a surface acoustic wave in an out-of-plane magnetized epilayer

Laura Thevenard·Ibrahima Sock Camara·Jean-Yves Prieur·Pauline Rovillain·Aristide Lemaître·Catherine Gourdon·Jean-Yves Duquesne
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Abstract

Inverse magnetostriction is the effect by which magnetization can be changed upon application of stress/strain. A strain modulation may be created electrically by exciting interdigitated transducers to generate surface acoustic waves (SAWs). Hence SAWs appear as a possible route towards induction-free undulatory magnetic data manipulation. Here we demonstrate experimentally on an out-of-plane magnetostrictive layer a reduction of the coercive field of up to 60$\%$ by a SAW, over millimetric distances. A simple model shows that this spectacular effect can be partly explained by the periodic lowering of the strain-dependent domain nucleation energy by the SAW. This proof of concept was done on (Ga,Mn)(As,P), a magnetic semiconductor in which the out-of-plane magnetic anisotropy can be made very weak by epitaxial growth; it should guide material engineering for all-acoustic magnetization switching.

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Laura Thevenard, Ibrahima Sock Camara, Jean-Yves Prieur, Pauline Rovillain, Aristide Lemaître, Catherine Gourdon, Jean-Yves Duquesne. 2016-02-29. Strong reduction of the coercivity by a surface acoustic wave in an out-of-plane magnetized epilayer. https://doi.org/10.1103/physrevb.93.140405

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