Ion implantation engineering of Si-Mn alloys with high-temperature ferromagnetism

• Applicant: Dr. Shengqiang Zhou
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2015 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 260481135

Realizing a Si-based magnetic semiconductor or alloy would advance the development of semiconductor spintronics due to the availability of high quality, large-size, and low-cost wafers. More importantly, the fabrication of Si:Mn systems is compatible with the mature microelectronics technology. In our preliminary research, we have used ion implantation, the conventional doping method of Si, to introduce Mn ions in Si substrates. We have embedded MnSi1.7 magnetic nanocrystals inside the Si matrix. Compared with the bulk form, MnSi1.7 nanocrystals exhibit a much larger magnetic moment. Our international cooperation partner at the Kurchatov Institute has prepared non-stoichiometric SiMn alloys exhibting room temperature ferromagnetism and anomalous Hall effect. The slight excess of Mn and the resulted defects are proposed to be the origin of the exotic magnetic properties compared with the stoichiometric compound. The proposed project leverages the unique capabilities and research experience at both research groups. We will use ion implantation to finely tune the stoichiometry of Si-Mn alloy films and to introduce defects as well. The two groups will work together to (1) prepare Si-Mn alloys possessing high-temperature ferromagnetism with the engineering possibility by ion implantation; and (2) to reveal the mechanisms of the ferromagnetic order by comprehensive investigations of the magnetic, structural and transport properties of these alloys. Fabrication of a prototype device for spintronic applications and a search for a signature of magnetic skyrmions will also be attempted.

• DFG Programme: Research Grants
• International Connection: Russia
• Partner Organisation: Russian Foundation for Basic Research
• Participating Persons: Muhammad Khalid, Ph.D.; Dr. Slawomir Prucnal; Professor Vladimir Rylkov; Ye Yuan