Vector imaging of electric field-induced reversible magnetization reversal in exchange-biased multiferroic heterostructures

Abstract

Exchange bias between ferromagnetic and antiferromagnetic layers has been widely utilized in spintronic devices. Controlling the exchange bias in magnetic multilayers by an electric field (E-field) has been proposed as a low-power solution for manipulating the macroscopic properties such as exchange bias fields and magnetization values, while how the magnetic domains respond to the E-fields has rarely been reported in an exchange-biased system. Here, we realize the vector imaging of reversible electrical modulation of magnetization reversal in exchange-biased CoFeB/IrMn/PMN-PT (011) multiferroic heterostructures, utilizing in-situ quantitative magneto-optical Kerr effect (MOKE) microscopy. Under the electrical control, magnetic domains at −80 Oe rotate reversibly between around 160° and 80°–120°, whose transverse components reverse from 225° to 45° correspondingly. Moreover, pixel-by-pixel comparisons are conducted to further imply the reversible magnetization reversal by E-fields. E-field-induced reversible magnetization reversal is also demonstrated without applying external magnetic fields. Vector imaging of electrical manipulation of exchange bias is of great significance in understanding the magnetoelectric effect and the development of next-generation spintronic devices.