Magneto-ionic control of spin polarization in magnetic tunnel junctions

Abstract

Magnetic tunnel junctions (MTJs) with Hf0.5Zr0.5O2 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 10^6%. 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.

References in corpus (12)

• Physics of thin-film ferroelectric oxides
• Multiferroicity, The coupling between magnetic and polarization
• Giant sharp magnetoelectric switching in multiferroic epitaxial La_{0.67}Sr_{0.33}MnO_3 on BaTiO_3
• Tunneling electroresistance effect in ferroelectric tunnel junctions at the nanoscale
• A rhombohedral ferroelectric phase in epitaxially-strained Hf0.5Zr0.5O2 thin films
• Magneto-ionic Control of Interfacial Magnetism
• Carrier-mediated magnetoelectricity in complex oxide heterostructures
• Origin of the magnetoelectric coupling effect in Pb(Zr0.2Ti0.8)O3/La0.8Sr0.2MnO3 multiferroic heterostructures
• Magnetization Reversal by Electric-Field Decoupling of Magnetic and Ferroelectric Domains Walls in Multiferroic-Based Heterostructures
• Growth Window of Ferroelectric Epitaxial Hf0.5Zr0.5O2 Thin Films
• Unraveling ferroelectric polarization and ionic contributions to electroresistance in epitaxial Hf0.5Zr0.5O2 tunnel junctions
• Magnetic tunnel junctions based on ferroelectric Hf0.5Zr0.5O2 tunnel barriers

Cited by in corpus (5)

• Epitaxial Ferroelectric HfO2 Films: Growth, Properties, and Devices
• High polarization, endurance and retention in sub-5 nm Hf${}_{0.5}$Zr${}_{0.5}$O${}_2$ films
• Polarization and resistive switching in epitaxial 2 nm Hf${}_{0.5}$Zr${}_{0.5}$O${}_2$ tunnel junctions
• Stabilization of the epitaxial rhombohedral ferroelectric phase in ZrO2 by surface energy
• Investigating the Electromechanical Behavior of Unconventionally Ferroelectric $H{f}_{0.5}Z{r}_{0.5}{O}_2$-based Capacitors Through Operando Nanobeam X-ray Diffraction