Giant spin-orbit magnetic state readout enhanced by a magnetic tunnel junction

Abstract

Magnetoelectric spin-orbit (MESO) logic, composed of a voltage-controlled magnetoelectric writing module and a spin-orbit readout module, is highly expected to substitute the silicon-based transistors and enable energy-efficient and scalable computing. Nevertheless, the output voltage of readout module based on spin-to-charge conversion is far less than the minimum magnetoelectric writing voltage, which greatly restricts the cascading function of MESO logic. Here, we first propose a magnetic tunnel junction (MTJ)-enhanced MESO logic to implement giant readout signal. Up to 1.5 mV output voltage is obtained, marking a significant improvement of approximately two orders of magnitude compared to previous findings. We ascribe the substantial enhancement to current modulation by junction resistance and the spin filtering effect of MgO-based MTJ. Moreover, the naturally integrated MTJ and MESO enables instantaneous and nonvolatile data exchange between computing module and external unit. Our work not only enhances output signal of readout module for direct cascading of MESO logic but also refines the design architecture, marking a pivotal stride forward in propelling MESO technology toward practical applications.