FePd₂Te₂: An Anisotropic Two-Dimensional Ferromagnet with One-Dimensional Fe Chains

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Magnetism

Background:

• Two-dimensional (2D) magnets are crucial for fundamental physics and spintronic applications.
• The search for novel 2D magnetic materials with unique properties is ongoing.

Purpose of the Study:

• To report the discovery and characterization of a new ternary compound, FePd₂Te₂.
• To investigate its structural, electronic, and magnetic properties for potential applications.

Main Methods:

• Crystal growth of centimeter-sized FePd₂Te₂ single crystals.
• Density functional theory (DFT) calculations, mechanical exfoliation, and atomic force microscopy (AFM) for structural analysis.
• Magnetic characterization including magnetoresistance, anomalous Hall effect, and specific heat measurements.

Main Results:

• FePd₂Te₂ possesses a layered quasi-2D crystal structure with 1D Fe zigzag chains.
• It can be exfoliated down to ~5 nm thickness, exhibiting easy-plane ferromagnetism with a Curie temperature (Tc) of ~183 K.
• Strong in-plane uniaxial magnetic anisotropy, large coercivity, and a significant electronic specific heat coefficient (γ ~ 32.4 mJ mol⁻² K⁻²) were observed.
• Scanning tunneling microscopy revealed crystal twinning leading to bent Fe chains and an intriguing spin texture.

Conclusions:

• FePd₂Te₂ is a novel correlated anisotropic 2D magnet with potential for multidisciplinary research.
• Its robust ferromagnetism at the nanoscale and unique spin texture make it a promising candidate for advanced spintronic devices.