Electronic and magnetic properties of silicene monolayer under bi-axial mechanical strain: a first-principles study

TL;DR

This study uses first-principles calculations to explore how biaxial strain affects the electronic and magnetic properties of Cr-doped silicene monolayers, revealing strain-dependent magnetic moments and electronic behaviors relevant for spintronics.

Contribution

It provides new insights into strain-induced modifications of magnetic and electronic properties in Cr-doped silicene, a novel 2D material for spintronic applications.

Findings

Cr doping results in metallic, half-metallic, or semiconducting behavior.

Magnetic moments are weakly affected by strain for monomer and vertical dimer substitutions.

Largest band gap of 0.13 eV occurs at zero strain for vertical Cr doping.

Abstract

Mechanical control of electronic and magnetic properties of 2D Van-der-Waals heterostructures gives new possibilities for further development of spintronics and information-related technologies. Using the density functional theory, we investigate the structural, electronic, and magnetic properties of silicene monolayer with substituted Chromium atoms and under a small biaxial strain ($-6\%< \epsilon < 8\%$). Our results indicate that the Cr-doped silicene nanosheets without strain have magnetic metallic, half-metallic or semiconducting properties depending on the type of substitution. We also show that the magnetic moments associated with the monomer and vertical dimer substitutions change very weakly with strain. However, the magnetic moment associated with the horizontal dimer substitution decreases when either compressive or tensile strain is applied to the system. Additionally, we show that the largest semiconductor band-gap is approximately 0.13 eV under zero strain for the vertical Cr-doped silicene. Finally, biaxial compressive strain leads to irregular changes in the magnetic moment for Cr vertical dimer substitution.