Title :
Electron Microscopy Study on Magnetic Flux Lines in Superconductors: Memorial to Akira Tonomura
Author :
Harada, Kanako ; Osakabe, N. ; Ono, Y.A.
Author_Institution :
Hitachi Central Res. Lab., Hatoyama, Japan
Abstract :
Using electron holography and coherent beam Lorentz microscopy, Akira Tonomura investigated the physics of magnetic flux lines, or vortices, in metal and high-temperature superconductors for more than 20 years. The methodology he developed for doing this made use of coherent electron waves from cold-emission (field-emission) sources and their quantum-mechanical phase shifts. Using 300-kV and 1-MV electron microscopes, Tonomura and his team clarified the dynamic behavior of magnetic flux lines in Pb and Nb superconductors and in high-temperature YBa2Cu3O7-δ and Bi2Sr2CaCu2O8 + δ superconductors. This memorial paper reviews the static and dynamic flux-line behaviors in superconductors as revealed by their results.
Keywords :
barium compounds; bismuth compounds; calcium compounds; electron holography; field emission electron microscopy; high-temperature superconductors; lead; magnetic flux; niobium; optical vortices; strontium compounds; yttrium compounds; Akira Tonomura; Bi2Sr2CaCu2O8+δ; Nb; Pb; YBa2Cu3O7-δ; coherent beam Lorentz microscopy; coherent electron wave; cold-emission source; electron holography; electron microscopy study; field-emission source; high-temperature superconductor; magnetic flux line; metal superconductor; quantum-mechanical phase shift; voltage 1 MV; voltage 300 kV; vortices; Electron microscopy; Magnetic domains; Magnetic flux; Magnetic force microscopy; Magnetic resonance imaging; Superconducting magnets; Electron holography; Lorentz microscopy; electron microscopy; magnetic flux lines; superconductivity; vortex;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2012.2232924
