Unconventional Anomalous Hall Effect Driven by Self-Intercalation in Covalent 2D Magnet Cr₂Te₃

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Covalent 2D magnets, exemplified by Cr2Te3, possess self-intercalated magnetic cations within transition-metal dichalcogenide layers.
• These materials offer unique control over magnetic order and spin texture, crucial for advanced spintronic devices.

Purpose of the Study:

• To elucidate the origin of the unconventional anomalous Hall effect (AHE) observed in Cr2Te3.
• To investigate the role of self-intercalation in dictating the AHE mechanism and electronic band structure.

Main Methods:

• Analysis of the anomalous Hall effect (AHE) hysteresis in Cr2Te3.
• Theoretical investigation of the electronic band structure, focusing on spin-orbit coupling and Weyl-like nodes.
• Correlation of AHE properties with the canting angles of self-intercalated Cr cations.

Main Results:

• The unconventional AHE in Cr2Te3, marked by humps and dips near the coercive field, arises from an intrinsic mechanism driven by self-intercalation.
• Multiple Weyl-like nodes, sensitive to Cr cation canting angles, emerge in the electronic band structure due to strong spin-orbit coupling.
• These nodes significantly contribute to Berry curvature and AHE conductivity, leading to temperature-dependent sign changes and additional features in AHE hysteresis.

Conclusions:

• The study provides strong evidence for the intrinsic origin of the unconventional AHE in Cr2Te3.
• Self-intercalation is confirmed as a critical factor for engineering AHE in complex 2D magnets, paving the way for novel spintronic devices.