Mn-Doped Sr/Si(111)-(3 × 2) HCC Surfaces: Antiferromagnetic Semiconductors for Spintronic Applications

Abstract

Manganese and manganese silicide as promising candidates for spintronic applications have attracted great interest in recent years. Here, we adopt Sr-induced Si(111)-(3 × 2) honeycomb-chain channel (HCC) surface as a template and perform a systematical study on the structural stability and magnetic and electronic properties of Mn-doped Sr/Si(111)-(3 × 2) HCC surfaces by ab initio calculations. Our energetic and kinetic results show two robust inserting structures M6 and H4, where Mn atoms are located below the honeycomb Si chain and on the top or hollow site of the Si(111) surface. Their high structural stabilities are attributed to the doped Mn atoms that saturate all the dangling bonds of Si(111) surface. In these two structures, Mn atoms prefer antiferromagnetic coupling with the same local magnetic moment of 3 μB. Electronic band structures and band-decomposed charge density distributions reveal that these two stable surface structures have a semiconducting characteristic with a surface band gap of 0.21–0.28 eV. This work provides an antiferromagnetic system for the possible application in spintronics.

Computational design of double transition metal MXenes with intrinsic magnetic properties

“…68 Besides the above merits, AFM semiconductors have great potential for nanoscale electronic devices because of the existence of intrinsic band gaps. 69 Very attractively, in this work, we found ten AFM semiconductors from the explored DTM MXenes. The M elements of these MCr 2 C 2 T 2 MXenes are situated at group IVB (M = Ti, Zr and Hf) of the periodic table.…”