Collective Magnetic Behavior in Vanadium Telluride Induced by Self-Intercalation

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Van der Waals (vdW) materials offer tunable magnetism via self-intercalation of magnetic atoms.
• Vanadium telluride is a promising vdW magnet with flexible nonstoichiometric compositions.
• Controlling magnetism in low-dimensional systems is crucial for spintronics.

Purpose of the Study:

• To investigate the atomic structure and magnetic behavior of V-rich V1+xTe2 nanoplates.
• To understand the role of self-intercalated vanadium in stabilizing magnetic phases.
• To explore strategies for manipulating magnetism in 2D materials for spintronic applications.

Main Methods:

• High-resolution scanning transmission electron microscopy (STEM).
• Density functional theory (DFT) calculations.
• Magnetometry measurements (hysteresis loops, temperature-dependent magnetization).
• Four-dimensional (4D) STEM diffraction imaging.

Main Results:

• V-rich V1+xTe2 nanoplates with embedded V3Te4 nanoclusters were synthesized via chemical vapor deposition (CVD).
• Self-intercalated V atoms stabilize a distorted 1T'-like monoclinic V3Te4 magnetic phase through electron doping.
• Nanoplates exhibit superparamagnetism, while nanoclusters show collective superspin-glass behavior at low temperatures.
• Diffuse magnetic domain structures were observed under high magnetic fields using 4D STEM.

Conclusions:

• Self-intercalation provides a pathway to control magnetism in 2D vdW materials.
• The observed magnetic behaviors (superparamagnetism, superspin-glass) are linked to the stabilized V3Te4 phase and nanocluster formation.
• Findings advance the understanding of dilute magnetism in 2D systems and inform spintronic device design.