Domain-Pattern Transfer across an Artificial Magnetoelectric Interface

Repeatable and reversible switching of magnetization by an electric field at room temperature is a prime goal of multiferroics research, and was recently achieved in BiFeO${}_{3}$/Co${}_{0.9}$Fe${}_{0.1}$ heterostructures. Unfortunately, the mechanism of this magnetoelectric switching process remain largely unexplored, as accessing the buried BiFeO${}_{3}$ domain state is difficult. The authors use a nondestructive optical method plus magnetic force microscopy to access the details of the system's magnetoelectric poling dynamics $i\phantom{\rule{0}{0ex}}n$ $o\phantom{\rule{0}{0ex}}p\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}d\phantom{\rule{0}{0ex}}o$, an essential step toward studying the ultrafast switching dynamics that are so important for device applications.