Electrical Control of Metallic Heavy-Metal–Ferromagnet Interfacial States

Abstract

Voltage control effects provide an energy-efficient means of tailoring material properties, especially in highly integrated nanoscale devices. However, only insulating and semiconducting systems can be controlled so far. In metallic systems, there is no electric field due to electron screening effects and thus no such control effect exists. Here we demonstrate that metallic systems can also be controlled electrically through ionic not electronic effects. In a Pt/Co structure, the control of the metallic Pt/Co interface can lead to unprecedented control effects on the magnetic properties of the entire structure. Consequently, the magnetization and perpendicular magnetic anisotropy of the Co layer can be independently manipulated to any desired state, the efficient spin toques can be enhanced about 3.5 times, and the switching current can be reduced about one order of magnitude. This ability to control a metallic system may be extended to control other physical phenomena. (a) EF x z H z

Electric field control on gated Pt/Co/SiO2 heterostructure with insulating polymer

“…We investigate the H c of the magnetic Hall crosses by varying the Co thickness (Co t ) and by using electric field control. These results support the mechanism of magneto-ionic effect which has been proposed due to the oxidation at the Co/oxide interface [16,18,19,23,25]. The results also indicate that a thinner polymer accelerates the magneto-ionic effect, leading to further possible optimization for high speed electric field control.…”

Nanoscale magnetization reversal by electric field-induced ion migration

“…Migration of ionic specie that either constitutes the magnetic structure or comes from the external sources can effectively lead to the Prospective Article magnetization modulation in ferromagnetic thin films, which is useful for realizing low power spintronic devices. [69] The construction of foreign magnetic conductive filaments in the insulating matrix also gives rise to TMR and AMR characteristics. Recently it is demonstrated that by accurately controlling the evolution dynamics and thus the dimension of the conductive filaments, NPC with quantized conductance characteristics can be obtained in resistive switching devices.…”

Significant Strain‐Induced Orbital Reconstruction and Strong Interfacial Magnetism in TiNi(Nb)/Ferromagnet/Oxide Heterostructures via Oxygen Manipulation

“…The PMA of FM/MO bilayers mainly derives from the interfacial FM 3d‐O 2p orbital hybridization that is sensitive to the interfacial oxygen environment . Therefore, extensive works were carried out to tailor the interfacial magnetism by controlling O 2− transport especially using an electric field . The electric field can drive O 2‐ migration to change oxidation state of FM layer, which can regulate the magnetic anisotropy energy (MAE), which paves a feasible way for markedly reducing the switching energy in solid‐state spintronic devices.…”

“…Therefore, extensive works were carried out to tailor the interfacial magnetism by controlling O 2− transport especially using an electric field . The electric field can drive O 2‐ migration to change oxidation state of FM layer, which can regulate the magnetic anisotropy energy (MAE), which paves a feasible way for markedly reducing the switching energy in solid‐state spintronic devices. However, to apply an effective electric field, a thick MO layer of tens of nanometers is required to ensure its good insulativity, which may restrict the application on devices with thin MO layers.…”