Determining the depth-profile of magnetoelectric coupling in multiferroic PMN-PT/FeRh using PNR

Multiferroic systems allow the modulation of magnetic properties through electric potentials. Advances in engineering atomic interfaces of heterogeneous thin-films have enabled a significant increase in magnetoelectric coupling compared with conventional single phase materials. This opens a range of interesting and exciting possibilities for new spintronic devices with applications in next-generation data storage technologies, such as antiferromagnetic memory resistors. One system with real potential is FeRh where a change in lattice parameter accompanies a change from anti- to ferro-magnetic ordering. Here we propose to use PNR to investigate this metamagnetic transition by manipulating the strain in FeRh thin films using ferroelectric PMN-PT substrates. The key objective of this work is to identify depth-dependent interplay between electric field and magnetic order in this system.

多铁性体系（Multiferroic systems）可借助电势对磁特性进行调控。近年来，异质薄膜原子界面工程的技术进展，使得磁电耦合强度相较于传统单相材料实现了显著提升。这为新型自旋电子器件开辟了诸多极具前景的创新可能，这类器件可应用于反铁磁存储电阻器等下一代数据存储技术领域。其中，FeRh合金是极具实际应用潜力的体系之一：其晶格参数的变化伴随着反铁磁有序向铁磁有序的转变。本研究拟采用极化中子反射法（Polarized Neutron Reflectometry，PNR），借助铁电PMN-PT衬底调控FeRh薄膜中的应变，以此探究该体系的变磁转变过程。本工作的核心目标是明确该体系中电场与磁有序之间的深度依赖相互作用。