Magneto-ionic control of magnetism using a solid-state proton pump

Voltage-gated ion transport as a means of manipulating magnetism electrically could enable ultralow-power memory, logic and sensor technologies. Earlier work made use of electric-field-driven O2− displacement to modulate magnetism in thin films by controlling interfacial or bulk oxidation states. However, elevated temperatures are required and chemical and structural changes lead to irreversibility and device degradation. Here we show reversible and non-destructive toggling of magnetic anisotropy at room temperature using a small gate voltage through H+ pumping in all-solid-state heterostructures. We achieve 90° magnetization switching by H+ insertion at a Co/GdOx interface, with no degradation in magnetic properties after >2,000 cycles. We then demonstrate reversible anisotropy gating by hydrogen loading in Pd/Co/Pd heterostructures, making metal–metal interfaces susceptible to voltage control. The hydrogen storage metals Pd and Pt are high spin–orbit coupling materials commonly used to generate perpendicular magnetic anisotropy, Dzyaloshinskii–Moriya interaction, and spin–orbit torques in ferromagnet/heavy-metal heterostructures. Thus, our work provides a platform for voltage-controlled spin–orbitronics.Hydrogen pumping is used to reversibly modulate magnetic anisotropy in solid-state heterostructures.

[1]  Uwe Bauer,et al.  Voltage-controlled domain wall traps in ferromagnetic nanowires. , 2013, Nature nanotechnology.

[2]  K. Kreuer.  Proton Conductivity: Materials and Applications , 1996 .

[3]  A. Fert,et al.  Anatomy of Dzyaloshinskii-Moriya Interaction at Co/Pt Interfaces. , 2015, Physical review letters.

[4]  Lei Bi,et al.  Steam electrolysis by solid oxide electrolysis cells (SOECs) with proton-conducting oxides. , 2014, Chemical Society reviews.

[5]  Qinghua Zhang,et al.  Electric-field control of tri-state phase transformation with a selective dual-ion switch , 2017, Nature.

[6]  M. Rubina,et al.  X-ray Absorption Spectroscopy of Transition Metal-Magnesium Hydride Thin Films , 2004 .

[7]  C. Campbell.  Catalyst-support interactions: Electronic perturbations. , 2012, Nature chemistry.

[8]  Ping Liu,et al.  Water gas shift reaction on Cu and Au nanoparticles supported on CeO2(111) and ZnO(0001): intrinsic activity and importance of support interactions. , 2007, Angewandte Chemie.

[9]  T. Oda,et al.  Finite electric field effects in the large perpendicular magnetic anisotropy surface Pt/Fe/Pt(001): a first-principles study. , 2009, Physical review letters.

[10]  D. Lederman,et al.  Effects of hydrogen/deuterium absorption on the magnetic properties of Co/Pd multilayers , 2011, 1102.2260.

[11]  A. K. Mohanty,et al.  A First Principles Study , 2012 .

[12]  Wei D. Lu,et al.  Nanoscale electrochemistry using dielectric thin films as solid electrolytes. , 2016, Nanoscale.

[13]  Masashi Shiraishi,et al.  Voltage-Assisted Magnetization Switching in Ultrathin Fe80Co20 Alloy Layers , 2009 .

[14]  J. Nørskov,et al.  Electrolysis of water on (oxidized) metal surfaces , 2005 .

[15]  Pritish Narayanan,et al.  Neuromorphic computing using non-volatile memory , 2017 .

[16]  Junhao Chu,et al.  Surface magnetoelectric effect in ferromagnetic metal films. , 2008, Physical review letters.

[17]  J. Bokhoven,et al.  Particle Size Effect of Hydride Formation and Surface Hydrogen Adsorption of Nanosized Palladium Catalysts: L3 Edge vs K Edge X-ray Absorption Spectroscopy , 2009 .

[18]  A. Züttel,et al.  Hydrogen-storage materials for mobile applications , 2001, Nature.

[19]  Qinghua Zhang,et al.  Electric-field control of ferromagnetism through oxygen ion gating , 2017, Nature Communications.

[20]  Takayoshi Katase,et al.  A transparent electrochromic metal-insulator switching device with three-terminal transistor geometry , 2016, Scientific Reports.

[21]  Massimiliano Di Ventra,et al.  Experimental demonstration of associative memory with memristive neural networks , 2009, Neural Networks.

[22]  J. Borchers,et al.  Controllable positive exchange bias via redox-driven oxygen migration , 2016, Nature Communications.

[23]  R. Waser,et al.  Effects of Moisture on the Switching Characteristics of Oxide‐Based, Gapless‐Type Atomic Switches , 2012 .

[24]  Hui Wu,et al.  Lithium-Ion Battery Cycling for Magnetism Control. , 2016, Nano letters.

[25]  Dusan Strmcnik,et al.  Energy and fuels from electrochemical interfaces. , 2016, Nature materials.

[26]  L. Hammer,et al.  Reversible H-induced switching of the magnetic easy axis in Ni/Cu(001) thin films. , 2004, Physical review letters.

[27]  N. Tamura,et al.  X-ray absorption spectroscopy of transition metal-magnesium hydride thin films , 2003 .

[28]  Y. Larring,et al.  Hydrogen in oxides. , 2004, Dalton transactions.

[29]  Zhengya Zhang,et al.  A Native Stochastic Computing Architecture Enabled by Memristors , 2014, IEEE Transactions on Nanotechnology.

[30]  K. Nielsch,et al.  Electrochemical and in situ magnetic study of iron/iron oxide films oxidized and reduced in KOH solution for magneto-ionic switching , 2016 .

[31]  Hua Zhou,et al.  Ion-gel-gating-induced oxygen vacancy formation in epitaxial L a 0.5 S r 0.5 Co O 3 -δ films from in operando x-ray and neutron scattering , 2017 .

[32]  Parkin,et al.  Oscillatory magnetic exchange coupling through thin copper layers. , 1991, Physical review letters.

[33]  J. Borchers,et al.  Reversible Control of Magnetism in La0.67Sr0.33MnO3 through Chemically-Induced Oxygen Migration , 2016 .

[34]  H. Hahn,et al.  Toward On‐and‐Off Magnetism: Reversible Electrochemistry to Control Magnetic Phase Transitions in Spinel Ferrites , 2016 .

[35]  William R. Oates,et al.  Materials and applications , 1996 .

[36]  Yidong Xia,et al.  Cathode bubbles induced by moisture electrolysis in TiO2−x-based resistive switching cells , 2016 .

[37]  A. Marcelli,et al.  Palladium L3 absorption edge of PdH0.6 films: Evidence for hydrogen induced unoccupied states , 1989 .

[38]  J. Fuggle,et al.  Electronic structure and surface kinetics of palladium hydride studied with x-ray photoelectron spectroscopy and electron-energy-loss spectroscopy , 1982 .

[39]  Uwe Bauer,et al.  Magneto-ionic control of interfacial magnetism. , 2014, Nature materials.

[40]  Run‐Wei Li,et al.  In Situ Nanoscale Electric Field Control of Magnetism by Nanoionics , 2016, Advanced materials.

[41]  B. Adams,et al.  The role of palladium in a hydrogen economy , 2011 .

[42]  C. Frisbie,et al.  Electrostatic versus Electrochemical Doping and Control of Ferromagnetism in Ion-Gel-Gated Ultrathin La0.5Sr0.5CoO3-δ. , 2016, ACS nano.

[43]  A. Tulapurkar,et al.  Large voltage-induced magnetic anisotropy change in a few atomic layers of iron. , 2009, Nature nanotechnology.

[44]  J. Maier,et al.  On the proton conductivity in pure and gadolinium doped nanocrystalline cerium oxide. , 2011, Physical chemistry chemical physics : PCCP.

[45]  D. Attwell,et al.  Synaptic Energy Use and Supply , 2012, Neuron.

[46]  Influence of controlled surface oxidation on the magnetic anisotropy of Co ultrathin films , 2015 .

[47]  A. Bollinger,et al.  Insulator to metal transition in WO3 induced by electrolyte gating , 2014, 1707.05748.

[48]  S. Zalkind,et al.  The interaction of O2 with the surface of polycrystalline gadolinium at the temperature range 300–670 K , 2011 .

[49]  A. Hoffmann.  Spin Hall Effects in Metals , 2013, IEEE Transactions on Magnetics.

[50]  Kai Liu,et al.  Structural and magnetic depth profiles of magneto-ionic heterostructures beyond the interface limit , 2016, Nature Communications.

[51]  Shufeng Zhang,et al.  Reversible control of Co magnetism by voltage-induced oxidation. , 2014, Physical review letters.

[52]  Chun-Gang Duan,et al.  Electric field effect on magnetization at the Fe/MgO(001) interface , 2010 .