Tokura and his team accomplished their direct observation of skyrmions by using a Lorentz transmission electron microscope, which is suited to image magnetic structures at very high resolution. Previously, physicists considered this type of experiment impossible because observing skyrmions would require the application of external magnetic fields that they thought would disturb the imaging process of the microscope. The team realized, however, that this problem could be overcome by applying the external magnetic fields perpendicular to the imaging lens of the microscope. Tokura says that this led to the breakthrough that allowed them to show the emergence of skyrmions unambiguously.
Wednesday, September 1, 2010
First direct observation of unusual magnetic structure could lead to novel electronic, magnetic memory devices
First direct observation of unusual magnetic structure could lead to novel electronic, magnetic memory devices: A skyrmion can be envisaged as a vortex-like arrangement of magnetic moments that, towards the center of the structure, increasingly twist and bend in downwards direction. In earlier experiments by other research groups, the existence of skyrmions had been inferred indirectly but efforts to image them, and to confirm their structure, failed owing to their small size with diameters of around 90 nanometers.