The precise control and stabilization of magnetic domain walls is key for the development of the next generation magnetic nanodevices. Using XMCD-PEEM, we have observed a topologically protected magnetic domain wall in a ferromagnetic cylindrical nanowire. Its structure is stabilized by periodic sharp alterations of the chemical composition in the nanowire. The large stability of this topologically protected domain wall contrasts with the mobility of other non-protected and non-chiral states also present in the same nanowire. These results are relevant for the design of future spintronic devices such as domain wall based RF oscillators or magnetic memories.

See: Sci. Rep. 8 (2018) 16695

Research Lines

We have interests in three main research lines, mainly focused on the study of the fundamental properties and applications of electrodeposited nanowires.

Domain wall spintronics. We study the domain wall structure and the magnetization processes of low dimensional systems - mainly cylindrical nanowires. We are interested in stabilizing domain walls in artificially created defects (Sci. Rep. 8 (2018) 16695) and in controlling the deepining of the different domain walls, induced by magnetic fields and by spin-polarized currents. Understanding the dynamics in arrays of nanowires would allow us to incorporate these nanostructures in spintronics devices. Part of this research is carried out in synchrotron radiation facilities (Nanoscale 10 (2018) 5566).

Transport properties of Bi-based materials. Bi-based metallic nanowires provide an attractive scenario for fundamental investigation of finite-size effects due to the unusual electronic structure of Bi and the large spin-orbit coupling of Bi atoms. We have already synthesized single-crystal Bi nanowires and reported weak antilocalization effects in the magnetotransport properties (Appl. Phys. Lett. 96 (2010) 082110). Now, we focus our interest on the synthesis of Bi-doped metallic nanowires. This system is expected to show large spin mixing conductance, as we have already reported in thin films (APL Materials 6 (2018) 101107).

Nanowires for applications. We prepare nanowires in solution for different applications, from chemical sensors (RSC Adv. 5 (2015) 97503-97507) to biomedical applications (J. Phys. Chem. C. 121 (2017) 23158-23165). We are also developing arrays of metallic nanowires that can be used as active part of nanostructured electrodes in neural interfaces.