Voltage controlled exchange bias in an all-thin-film Cr$_{2}$O$_{3}$ based heterostructure*

Spintronics utilizes the electron's spin degree of freedom for an advanced generation of electronic devices with novel functionalities. Controlling magnetism by electrical means has been identified as a key challenge in the field of spintronics, and electric control of exchange bias is one of the most promising routes to address this challenge. Previously, robust isothermal electric control of exchange bias has been achieved near room temperature utilizing a bulk single crystal of Cr$_{2}$O$_{3}$ [1,2]. In this study electric control of exchange bias in an all-thin-film system is demonstrated with significant implications for device realization. In particular, voltage controlled switching of exchange bias in a Cr$_{2}$O$_{3}$ based magnetoelectric magnetic tunnel junction enables nonvolatile memory storage with virtually dissipationless writing at, or above, room temperature. Additionally, unique physical properties which arise due to the Cr$_{2}$O$_{3}$ thin film geometry are highlighted.\\[4pt] [1] Xi He, et. al, Nat. Mater. 9, 579-585 (2010)\\[0pt] [2] W. Echtenkamp, Ch. Binek, Phys. Rev. Lett. 111, 187204 (2013)