An ultralow power magnetoelectric nonvolatile memory*

Most modern computing is built upon the von Neumann architecture composed of the data storage and data operation in a central processing unit. However, as Moore’s law made exponential gains over the decades, a memory bottleneck emerged, also known as the von Neumann bottleneck. This memory bottleneck can often degrade computing by orders of magnitude below the maximum potential of the computer especially for applications with large data sets. Hence it is of great interest to develop new energy-efficient memory technologies. Spintronic memory based on spin-transfer torque has emerged as a potential on-chip memory but it suffers from high energy dissipation (due to the requirement for a large current) and high voltages (due to the use of tunnel junctions). In contrast, a magneto-electric memory can operate with a capacitive displacement charge and potentially reach a 1-10 aJ/switching operation. Here we show magneto-electric switching of a memory element with a giant magnetoresistance (GMR) readout, operating at ~200 mV. We utilize a combination of phase detuning via isovalent substitution, thickness scaling, and conductive oxide electrode choice to scale the switching energy density to 20 µJ/cm². To the best of our knowledge, this is among the lowest voltage and energy density demonstrated in a spintronic memory element, thus presenting an attractive pathway to ultralow-power electronics.