Zr₂Si: an antiferromagnetic Dirac MXene

Area of Science:

• Materials Science
• Condensed Matter Physics
• Quantum Chemistry

Background:

• MXenes are a class of 2D materials with graphene-like properties, crucial for nanoelectronics.
• Most MXenes are metallic or semiconducting; Dirac cones, like those in graphene, are rare.
• Exploring novel MXenes with unique electronic properties is vital for technological advancement.

Purpose of the Study:

• To propose and investigate a new MXene, Zr₂Si, for potential nanoelectronic applications.
• To identify and characterize the electronic band structure of Zr₂Si, particularly the presence of Dirac cones.
• To explore the tunability of Zr₂Si's electronic properties through spin-orbit coupling and electron correlation.

Main Methods:

• First-principles calculations were employed to simulate and analyze the material properties.
• Density Functional Theory (DFT) was used to determine the ground state and electronic structure.
• Analysis of orbital contributions to the electronic band structure was performed.

Main Results:

• A new MXene, Zr₂Si, was proposed with an antiferromagnetic ground state.
• Anisotropic Dirac cones with Fermi velocities comparable to graphene were observed in Zr₂Si.
• The Dirac spectrum originates primarily from the dₓ and d<0xE2><0x82><0x91> orbitals of Zr atoms.
• Spin-orbit coupling (SOC) and Coulomb interaction (U) were shown to gap the Dirac cones.

Conclusions:

• Zr₂Si is a promising candidate for future nanoelectronic devices.
• The tunable electronic properties of Zr₂Si, particularly the gapped Dirac cones, offer new possibilities for electronic applications.
• This discovery expands the family of MXene materials with exotic electronic properties.