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Since the revival of multiferroic laminates with giant magnetoelectric (ME) coefficients, a variety of multifunctional ME devices, such as sensor, inductor, filter, antenna etc. have been developed. Magnetoelastic materials, which couple the magnetization and strain together, have recently attracted ever-increasing attention due to their key roles in ME applications. This review starts with a brief introduction to the early research efforts in the field of multiferroic materials and moves to the recent work on magnetoelectric coupling and their applications based on both bulk and thin-film materials. This is followed by sections summarizing historical works and solving the challenges specific to the fabrication and characterization of magnetoelastic materials with large magnetostriction constants. After presenting the magnetostrictive thin films and their static and dynamic properties, we review micro-electromechanical systems (MEMS) and bulk devices utilizing ME effect. Finally, some open questions and future application directions where the community could head for magnetoelastic materials will be discussed.

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The strong strain-mediated magnetoelectric (ME) coupling found in thin-film ME heterostructures has attracted an ever-increasing interest and enables realization of a great number of integrated multiferroic devices, such as magnetometers, mechanical antennas, RF tunable inductors and filters. This paper first reviews the thin-film characterization techniques for both piezoelectric and magnetostrictive thin films, which are crucial in determining the strength of the ME coupling. After that, the most recent progress on various integrated multiferroic devices based on thin-film ME heterostructures are presented. In particular, rapid development of thin-film ME magnetometers has been seen over the past few years. These ultra-sensitive magnetometers exhibit extremely low limit of detection (sub-pT/Hz1/2) for low-frequency AC magnetic fields, making them potential candidates for applications of medical diagnostics. Other devices reviewed in this paper include acoustically actuated nanomechanical ME antennas with miniaturized size by 1–2 orders compared to the conventional antenna; integrated RF tunable inductors with a wide operation frequency range; integrated RF tunable bandpass filter with dual H- and E-field tunability. All these integrated multiferroic devices are compact, lightweight, power-efficient, and potentially integrable with current complementary metal oxide semiconductor (CMOS) technology, showing great promise for applications in future biomedical, wireless communication, and reconfigurable electronic systems.

Since the discovery of strong magnetoelectric (ME) coupling in two‐phase ME laminate composites, strain mediated ME heterostructures have found practical applications in magnetic sensors, tunable inductors, tunable filters, miniaturized antennas, magnetic memories, and nanoscale motors. Thin film ME sensors, in particular, have become promising candidates in biomagnetic sensing, due to their high sensitivity, CMOS compatibility, room temperature operation, and high spatial resolution. In this article, an overview is presented on different types of thin film ME sensors and their applications in biomagnetic measurement. First, the coupling structures, materials selection, and fabrication processes are introduced. Three different mechanisms of recently emerged ME sensors, including the magnetic modulation, electrical modulation, and delta‐E effect are presented. Their performance and noise analysis are also compared and discussed. Finally, real‐time applications of ME sensors in the detection of magnetic fields from different part of human body are presented and discussed. The review concludes with an outlook on future perspectives and challenges of thin film ME sensors for biomagnetic applications.