[12p-N303-1~11] 13.6 Nanostructures, quantum phenomena, and nano quantum devices

▲ [12p-N303-3] Observation of four regions in the electromigration process of Ni nanojunctions

〇(D)Tian Yue¹, Shaoqing Du¹, Kazuhiko Hirakawa^1,2 (1.IIS, Univ.of Tokyo, 2.INQIE,Univ.of Tokyo)

Keywords:electromigration, nanojunction, ferromagnetic material

To add novel functions to molecular spintronic devices, the use of ferromagnetic electrodes has been attracting considerable attention to investigate quantum states at the single molecule level. However, fabrication of ferromagnetic (FM) nanogap electrodes by electrical break junction (EBJ) method and formation of single molecule transistors with FM electrodes have been difficult mainly because of the high melting temperatures of FM metal species. Therefore, it is necessary to clarify the elementary processes of EBJ process for FM nanojunctions.
In this work, we have applied the feedback controlled EBJ process to Ni nanojunctions in vacuum at 4.2K. We observed four different regions in the electromigration process from the corresponding Vc - Rj curve. Interestingly, two new regions are different from those in gold nanojunctions. At the conference, we will discuss more about the mechanism.