Departamento de Física promove colóquio nesta sexta-feira (27)
O evento acontecerá no auditório do Departamento, às 16h
O Departamento de Física (DF) da UFPE realizará, nesta sexta-feira (27), o colóquio “Modulated Cylindrical Magnetic Nanowires: from synthesis and magnetic characterization to technological applications”. O palestrante do evento será o professor Manuel Vázquez, do Instituto de Ciencia de Materiales de Madrid. O coloquio acontecerá no auditório do DF, às 16h.
Magnetic nanowires with engineered geometry and composition are attracting much attention owing to the fundamental phenomena associated to their curvature, and to their technological applications based on the magnetization reversal mechanisms. An overview of applications will be introduced, from advanced spintronics and logic devices, to magnetic sensors and biomagnetic functionalization.Then, most recent results of the investigation in our team will be overviewed. That includes particularly the design and electrochemical synthesis of arrays of magnetic nanowires (i.e. 20 to 200 nm diameter, 1 to 50 micrometer length; FeCoNi-based composition). The magnetization process in individual nanowires with controlled modulations in diameter or composition (i.e., multilayered) is experimentally characterized by Magnetic Force Microscopy, magneto-optical Kerr effect, PEEM/XMCD and Electron Holography. Micromagnetic simulations complete the studies for a deeper interpretation of the experimental results. As an example, the Figure below shows the recent observation of magnetization ratchet in multisegmented FeCo/Cu nanowires with designed increasing length of magnetic segments (images of the reversal process: simulated, left, and PEEM/XMCD, right; ACS Nano 2018, 12, 5932) of interest for the controlled motion of domain wall application to magnetic registers. The figure shows an example of FeCo diameter-modulated nanowires where the presence of complex domain structure is simulated and the “corkscrew” mechanism introduced, where the presence of skyrmions tubes is anticipated (Nanoscale, 2018, 10, 5923).
Departamento de Física - UFPE