Illustration: Carin Cain

Figure 1: Sketch of a magnetoelectric write head for magnetic hard disk (after A. K. Zvezdin [5]). An electric field $E$ generates a bulk magnetic moment $ΔmME$ in a slab of magnetoelectric material, thus giving rise to a magnetic flux density $B$. The gap in the flux closing yoke emits a stray field, which writes a magnetic “bit” into the moving track (velocity $ν$) of the hard disk.