Intrinsic half-metallicity in two-dimensional Cr₂TeX₂ (X = I, Br, Cl) monolayers

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) materials with intrinsic half-metallicity are essential for advanced spintronic devices.
• Experimental realization of such 2D materials at room temperature remains a significant challenge.

Purpose of the Study:

• To predict and theoretically investigate a new family of 2D materials, Cr2TeX2 (X = I, Br, Cl) monolayers.
• To assess their potential for half-metallicity and stability for spintronic applications.

Main Methods:

• First-principles calculations were employed to predict the material properties.
• Phonon spectrum calculations and molecular dynamics simulations were used to verify stability.
• Monte Carlo simulations were performed to determine Curie temperatures.

Main Results:

• Ferromagnetic (FM) half-metallic states were found to be energetically favorable for all Cr2TeX2 monolayers.
• Phonon and molecular dynamics simulations confirmed the stability of these FM states.
• Calculated Curie temperatures (486 K for Cr2TeI2, 445 K for Cr2TeBr2, 451 K for Cr2TeCl2) and half-metallic bandgaps (1.72–1.90 eV) indicate room-temperature functionality.
• Significant magnetocrystalline anisotropy energies (MAEs) were determined, with varying easy axis orientations.

Conclusions:

• The predicted 2D Cr2TeX2 monolayers exhibit stable intrinsic half-metallicity at room temperature.
• These materials hold significant promise for experimental realization and application in next-generation spin nanodevices.