Gate-Tuned Interlayer Coupling in van der Waals Ferromagnet Fe_{3}GeTe_{2} Nanoflakes

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Weak interlayer coupling limits van der Waals (vdW) magnets in 2D spintronic devices.
• Fe3GeTe2 (FGT) is a vdW magnet with potential for spintronic applications.

Purpose of the Study:

• To investigate the modulation of interlayer coupling in FGT using a protonic gate.
• To explore the resulting magnetic properties, including exchange bias.

Main Methods:

• Protonic gating was used to intercalate protons into FGT nanoflakes.
• Interlayer magnetic coupling and exchange bias were measured under varying gate voltages.

Main Results:

• Proton intercalation significantly increases interlayer magnetic coupling in FGT.
• Protonated FGT nanoflakes exhibit significant exchange bias, including a rare zero-field cooled (ZFC) exchange bias up to 1.2 kOe.
• Strong interlayer coupling was achieved via proton intercalation.

Conclusions:

• Protonic gating is an effective method to enhance interlayer coupling in vdW magnets.
• The observed exchange bias opens new avenues for vdW magnet applications.
• This work broadens the application scope of vdW magnets.