Spin-orbit-induced gap modification in buckled honeycomb XBi and XBi₃ (X  =  B, Al, Ga, and In) sheets

Area of Science:

• Materials Science
• Condensed Matter Physics
• Quantum Chemistry

Background:

• Two-dimensional (2D) materials offer unique electronic properties.
• Exploring novel 2D materials is crucial for advancing electronic and spintronic applications.

Purpose of the Study:

• To predict the band structure and stability of XBi and XBi3 (X = B, Al, Ga, In) single sheets.
• To investigate the influence of spin-orbit coupling (SOC) and group-III elements on their electronic and topological properties.

Main Methods:

• First-principles calculations were employed to study the electronic band structure.
• The impact of spin-orbit coupling on band degeneracy and band gap nature was analyzed.

Main Results:

• Band gap values are tunable by SOC and the specific group-III element.
• GaBi and InBi exhibit band inversions and are identified as potential topological insulators with band gaps around 172 meV.
• Some buckled sheets show sizable band gaps suitable for room-temperature spintronics.

Conclusions:

• XBi and XBi3 represent new classes of 2D materials with tunable topological properties.
• SOC is essential for understanding the tunability and achieving spin degeneracy lifting.
• These materials hold promise for applications in next-generation spintronic devices operating at room temperature.