Two dimensional topological semimetals robust against to spin-orbital coupling

Area of Science:

• Condensed Matter Physics
• Materials Science

Background:

• Two-dimensional (2D) topological semimetals exhibit nontrivial Berry phases and topologically protected edge states.
• These materials are classified into Dirac, Weyl, and nodal-ring types based on band structure and symmetry.
• Research in this field has evolved from early studies of graphene.

Purpose of the Study:

• To provide a comprehensive review of the current research landscape in 2D topological semimetals.
• To survey theoretical and experimental advancements in 2D Dirac, Weyl, and nodal-ring semimetals.
• To outline future research directions and potential advancements in the field.

Main Methods:

• Literature review of theoretical and experimental studies on 2D topological semimetals.
• Analysis of band degeneracies, dispersion characteristics, and symmetry-protection mechanisms.
• Discussion of state-of-the-art calculation techniques for materials identification.

Main Results:

• Overview of the classification and properties of 2D topological semimetals (Dirac, Weyl, nodal-ring).
• Summary of theoretical and experimental progress in the field.
• Identification of key areas for future research, including materials discovery and classification expansion.

Conclusions:

• 2D topological semimetals are a rapidly advancing area with significant potential.
• Future research should focus on accelerating materials discovery and broadening classification schemes.
• Exploring new physical effects in these materials is crucial for future advancements.