Electronic and Spin‐Dependent Optical Properties of Fe‐Adsorbed Armchair Silicene/Silicane Superlattices

The electronic and optical properties of Fe‐adsorbed silicene/silicane superlattices (Fe‐SSSLs) with armchair interface are studied by first‐principles calculations. It is demonstrated that the SSSLs show spin polarization after adsorption of Fe atoms, and the bandgaps of different Fe‐SSSLs exhibit oscillatory behaviors with the width of silicene region. Except for (6,4)‐SSSL with a small total magnetic moment (about 0.06 μ_B cell⁻¹), all other Fe‐SSSLs have a total magnetization moment of 2.00 μ_B cell⁻¹, which comes from the 3d orbitals of Fe atom. Furthermore, there is a great enhancement of optical absorption in the infrared‐light region for Fe‐SSSLs, which is caused by the transition in a single spin channel due to Fe adsorption. The results show that Fe adsorption can tune the electronic and optical properties of armchair SSSLs effectively, which makes armchair Fe‐SSSLs attractive candidates for spin‐polarized photoelectric device applications.