Prospects of Electric Field Control in Perpendicular Magnetic Tunnel Junctions and Emerging 2D Spintronics for Ultralow Energy Memory and Logic Devices

Next-generation memory and logic devices require perpendicular magnetic tunnel junctions (MTJs) with small cell size, long retention, and most importantly, low-power operation. Spin transfer torque (STT) and spin-orbit torque (SOT) mechanisms are the most widely used switching mechanisms for magnetic tunnel junctions, but both require high write current densities, leading to significant energy consumption. Electric field control of MTJs offers a path to drastically lower energy requirements by enabling switching without current flow. Electric field control of magnetization can be realized in multiferroic heterostructures through voltage-controlled magnetic anisotropy (VCMA) in ferromagnets or voltage-controlled exchange coupling (VCEC) between two exchange-coupled ferromagnetic layers. In addition, these electric field-controlled mechanisms can also be integrated into existing STT or SOT devices to further reduce the operational energy. Additionally, hybrid approaches combining VCEC with SOT, as well as unconventional spin-orbit torque (USOT) in low-symmetry materials, offer promising strategies for field-free, ultralow-power switching. Moreover, atomically thin 2D van der Waals (vdW) materials provide an efficient and scalable platform for electric-field-driven magnetization manipulation. These emerging concepts push the limits of energy efficiency and enable new functionalities for memory and logic applications beyond conventional CMOS technology.