Real-Time Observation of the Dynamics of Vortices by Electron Microscopy

Individual magnetic vortices in superconductors have become dynamically observable by Lorentz microscopy in a field-emission transmission electron microscope. Because material defects can be simultaneously observed with this method, the flux pinning phenomena, which are indispensable for practical applications of superconductors, can be microscopically observed. It was revealed that, to increase the critical current, not only the elementary pinning force of defects but also the vortex–vortex interaction should be taken into consideration.