A NOVEL NANOELECTROMAGNETIC SYSTEM USING MULTIFERROIC/MAGNETOELECTRIC NI-NANO-CHEVRON/PMN-PT HETEROSTRUCTURE TO DEMONSTRATE AN ELECTRIC -FIELD -CONTROLLED PERMANENT MAGNETIC SINGLE -DOMAIN TRANSFORMATION

Abstract

In this paper, we report a novel nanoelectromagnetic system using multiferroic/magnetoelectric Ni-nanochevron/PMN-PT heterostructure to demonstrate an electric field -controlled permanent magnetic single-domain transformation. The heterostructure consists of a magnetostrictive Ni-nano-chevron, Pt top and bottom electrodes, and a piezoelectric PMN-PT substrate. In initial state (as demagnetized), the magnetization of the magnetic single domain is stably along the long axis of the nano-chevron. A magnetic field of 3000 Oe (along 45 degree of nano-chevron) is applied to magnetize the Ni-nano-chevron from stable single domain to metastable two-domains. After this, an electric field of 0.8MV/m is applied to the PMN-PT substrate to produce the converse magnetoelectric effect to transform the two-domains. After the electric field is removed, the two-domains are further transformed back to the single-domain. Finally, when comparing the domains before and after applying our approach, approximately 50 % of single-domains are successfully and permanently switched (i.e., magnetization-direction is permanently rotated 180 degrees).