In recent years, extensive research has been conducted on methods of controlling and switching magnetization without applying any external magnetic field—known as electrolyte-gated magnetoelectric actuation. This type of actuation has the potential to dramatically reduce power consumption in magnetic devices. The new review puts forth a comprehensive overview of such studies over the past two decades.

Navarro-Senent et al. present the different mechanisms responsible for voltage-driven magnetic actuation and the various effects observed in different materials, with the intent of supplying a baseline for future advancements.

Potential applications of such devices are also discussed, given magnetoelectric actuation has now been demonstrated in metallic, semiconducting and dielectric oxide thin films, and nano-porous structures. Energy-efficient spintronics and multi-state magnetic memories are listed by the authors among a wide range of possible applications for this phenomenon.

Electrolyte-gated magnetoelectric actuation has also shown promise in biomedical applications, where it can be used for wireless electric cell stimulation when applied in a liquid medium. Liquid electrolytes have been further developed for other special applications with advantages over solid-state electrolytes, such as the ability to generate ultra-high electric fields, enhance ion mobility, and easily penetrate into 3D nano-porous magnetic alloys and oxides.

Despite the numerous advances in recent years, many aspects of this phenomenon are not fully understood, including the mechanisms of the magnetoelectric actuation itself. In order to fully exploit the technological applications of magnetoelectric materials, further studies are needed including in-depth structural investigations, studies of all-solid configurations, and tests on magnetic semiconductors at higher temperatures.

Source: “Electrolyte-gated magnetoelectric actuation: Phenomenology, materials, mechanisms and prospective applications,” by Cristina Navarro-Senent, Alberto Quintana, Enric Menéndez, Eva Pellicer, and Jordi Sort, APL Materials (2019). The article can be accessed at