Quantitative Determination on Ionic-Liquid-Gating Control of Interfacial Magnetism.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Ionic-liquid gating offers a low-voltage method to tune interfacial properties of functional thin films.
• Understanding voltage-controlled magnetic anisotropy (VCMA) is crucial for spintronics.

Purpose of the Study:

• To quantitatively determine the VCMA in Au/[DEME]+[TFSI]-/Co field-effect transistor heterostructures.
• To investigate the gating effects and their impact on magnetic anisotropy.

Main Methods:

• In situ electron spin resonance (ESR) measurements to detect magnetic anisotropy changes.
• X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) to analyze gating mechanisms.

Main Results:

• A reversible change in magnetic anisotropy of up to 219 Oe was achieved with a low gating voltage of 1.5 V at room temperature.
• A record high VCMA coefficient of approximately 146 Oe V⁻¹ was obtained.
• Electrostatic doping and electrochemical reactions were identified as distinct gating effects.

Conclusions:

• The developed ionic-liquid-gating system enables strong interfacial magnetoelectric coupling.
• This approach offers practical advantages for the development of next-generation spintronic and electronic devices.