Emerging novel electronic structure in hydrogen-Arsenene-halogen nanosheets: A computational study

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Arsenene, a 2D allotrope of arsenic, has garnered interest for its unique electronic properties.
• Previous studies on double-side decorated arsenenes primarily focused on materials with zero band gaps.

Purpose of the Study:

• To investigate the stability and electronic structure of novel double-side decorated arsenenes, termed hydrogen-arsenene-halogen (H-As-X).
• To explore the impact of layer number on the electronic properties of H-As-Cl sheets.

Main Methods:

• First-principles calculations incorporating spin-orbit coupling.
• Phonon dispersion calculations to assess dynamic stability.
• Analysis of electronic band structure and frontier states.

Main Results:

• H-As-X nanosheets (except H-As-F) are dynamically stable.
• All H-As-X nanosheets exhibit direct band gaps, a significant departure from prior work.
• Multilayer H-As-Cl sheets demonstrate multi-Dirac cone characteristics, sensitive to layer number.
• Top and bottom layers predominantly control frontier states in thicker H-As-Cl structures.

Conclusions:

• A new pathway to transition arsenene from indirect to direct band gaps has been identified.
• The study reveals novel electronic behaviors in multilayer H-As-Cl, including multi-Dirac cones.
• These findings offer valuable insights for potential applications of decorated arsenene materials.