Abstract In this work, we present an investigation on the effects of thermal annealing on the magnetic response of Lithium Niobate/Fe samples. Fe thin films have been deposited on Lithium Niobate Z-cut ferroelectric substrates by vapor phase epitaxy. A series of annealing treatments were performed on the samples, monitoring the evolution of their magnetic properties, both at the surface and on the volume. The combination of structural, magnetic, chemical and morphological characterizations shows that the modification of the chemical properties, i.e. the phase decomposition, of the substrate upon annealing affects drastically the magnetic behavior of the interfacial Fe layer. By tuning the annealing temperature, the magnetic coercive field value can be increased by an order of magnitude compared to the as-grown value, keeping the same in-plane isotropic behavior. Since no evident differences were recorded in the Fe layer from the chemical point of view, we attribute the origin of this effect to an intermixing process between a fragment of the substrate and the Fe thin film upon critical temperature annealing, process that is also is responsible for the observed changes in roughness and morphology of the magnetic thin film.

中文翻译：

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不稳定铌酸锂衬底上铁薄膜中矫顽力的热辅助定制

摘要 在这项工作中，我们研究了热退火对铌酸锂/铁样品磁响应的影响。Fe 薄膜已经通过气相外延沉积在铌酸锂 Z 切割铁电衬底上。对样品进行了一系列退火处理，监测其表面和体积的磁性演变。结构、磁性、化学和形态特征的组合表明，退火时衬底的化学性质的改变，即相分解，极大地影响界面Fe层的磁行为。通过调整退火温度，矫顽磁场值可以比生长值增加一个数量级，保持相同的面内各向同性行为。由于从化学的角度来看 Fe 层中没有记录到明显的差异，我们将这种效应的起源归因于在临界温度退火时衬底碎片和 Fe 薄膜之间的混合过程，这也是负责的过程对于观察到的磁性薄膜粗糙度和形态的变化。