Multiferroic tunnel junctions (MFTJs) with Hf_0.5Zr_0.5O₂ barriers are reported to show both tunneling magnetoresistance effect (TMR) and tunneling electroresistance effect (TER), displaying four resistance states by magnetic and electric field switching. Here we show that, under electric field cycling of large enough magnitude, the TER can reach values as large as 10⁶%. Moreover, concomitant with this TER enhancement, the devices develop electrical control of spin polarization, with sign reversal of the TMR effect. Currently, this intermediate state exists for a limited number of cycles and understanding the origin of these phenomena is key to improve its stability. The experiments presented here point to the magneto-ionic effect as the origin of the large TER and strong magneto-electric coupling, showing that ferroelectric polarization switching of the tunnel barrier is not the main contribution.

据报道，具有Hf _0.5 Zr _0.5 O ₂势垒的多铁隧道结（MFTJs）既显示隧道磁阻效应（TMR），又显示隧道电阻效应（TER），通过磁场和电场切换显示四个电阻状态。在这里，我们表明，在足够大的电场循环下，TER可以达到高达10 ^6的值。％。此外，与此TER增强相伴的是，这些器件开发出了自旋极化的电控制功能，并实现了TMR效应的符号反转。当前，这种中间状态存在有限的循环次数，了解这些现象的起源是提高其稳定性的关键。这里介绍的实验指出，磁离子效应是大TER和强磁电耦合的起源，表明隧道势垒的铁电极化转换不是主要的贡献。