In the development of any type of magnetic field sensor based on magnetic films, special consideration must be given to the magnetic layer component. The presented work investigates the use of scalable flux closing magnetostrictive multilayers for inverse magnetoelectric sensors. In such a type of magnetic field sensor, highly sensitive AC and DC field detection relies on strong excitation of the incorporated magnetic layers by piezoelectrically driven cantilever oscillation at mechanical resonances. The provoked periodic flux change is influenced by the magnetic field to be measured and is picked up by a coil, which generates the measured output. The multilayered inverse magnetoelectric sensor is investigated with regard to linearity, noise behavior, and detection limit of DC and AC signals. A significant advancement for inverse magnetoelectric thin film sensors is demonstrated in this study. Using exchange bias stabilized magnetic multilayers with flux closure structures, detection limits are improved by an order of magnitude to less than 8 pT/Hz1/2 at 10 Hz and 18 pT/Hz1/2 at DC.

中文翻译：

---

低噪声逆磁电磁场传感器

在开发任何类型的基于磁性薄膜的磁场传感器时，必须特别考虑磁性层组件。所提出的工作研究了可扩展磁通闭合磁致伸缩多层膜在逆磁电传感器中的使用。在这种类型的磁场传感器中，高灵敏度的交流和直流场检测依赖于机械共振时压电驱动的悬臂振荡对所结合的磁性层的强烈激励。引起的周期性磁通变化受到待测磁场的影响，并被线圈拾取，从而生成测量输出。研究了多层逆磁电传感器的线性度、噪声行为以及直流和交流信号的检测极限。这项研究证明了逆磁电薄膜传感器的重大进步。使用具有磁通闭合结构的交换偏置稳定磁性多层，检测限提高了一个数量级，在 10 Hz 时低于 8 pT/Hz1/2，在 DC 时低于 18 pT/Hz1/2。