Electrical Control of Magnetic Order Transition in 2D Antiferromagnetic Semiconductor FePS₃

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Controlling magnetic order in 2D materials is crucial for spintronic devices.
• Carrier concentration modulation is an effective method for tuning magnetic properties.

Purpose of the Study:

• To investigate the magnetic ground state transitions in 2D FePS3 via electron doping.
• To explore the potential for electrical control of magnetism in 2D materials.

Main Methods:

• Intercalation of organic cations to achieve electron doping of FePS3.
• Experimental characterization of magnetic properties (Curie temperature, anisotropy, hysteresis).
• Theoretical calculations (density functional theory) to understand electronic structure and magnetic ordering.

Main Results:

• Achieved reversible antiferromagnetic (AFM) to ferrimagnetic (FIM) to AFM transitions in FePS3 through controlled electron doping.
• The FIM phase exhibits a Curie temperature of ~110 K and strong out-of-plane magnetic anisotropy.
• Observed an unusual temperature-dependent magnetic hysteresis loop in the FIM phase.
• Theoretical calculations confirmed the doping concentration dependence of magnetic order (FIM at 0.3-0.9 electrons/cell, AFM at >= 1.0 electrons/cell).

Conclusions:

• Electron doping provides an effective route to engineer magnetism in 2D materials like FePS3.
• The observed AFM-FIM-AFM transition is driven by the competition between Stoner and super-exchange interactions.
• Demonstrated a pathway for electrical control of magnetic states for future spintronic applications.